CA1087597A - Production of allylic alcohols - Google Patents
Production of allylic alcoholsInfo
- Publication number
- CA1087597A CA1087597A CA281,793A CA281793A CA1087597A CA 1087597 A CA1087597 A CA 1087597A CA 281793 A CA281793 A CA 281793A CA 1087597 A CA1087597 A CA 1087597A
- Authority
- CA
- Canada
- Prior art keywords
- cadmium
- silver
- alloy
- accordance
- catalyst
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
- C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
- C07C29/143—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of ketones
- C07C29/145—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of ketones with hydrogen or hydrogen-containing gases
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
- B01J23/66—Silver or gold
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
- C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
- C07C29/14—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of a —CHO group
- C07C29/141—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of a —CHO group with hydrogen or hydrogen-containing gases
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Catalysts (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
This invention provides an improved hydrogenation process for converting an .alpha.,.beta.-olefincially unsaturated carbonylic compound into the corresponding allylic alcohol derivative which comprises reacting and .alpha.,.beta.-olefinically unsaturated carbonylic compound with hydrogen in the vapor phase at a temperature between about 0°C and 300°C and a pressure between about 15 and 15,000 psi in the presence of a catalyst comprising a silver-cadmium alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the alloy exhibits and X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines.
Acrolein is hydrogenated to allylic alcohol at high conversions and high yields.
This invention provides an improved hydrogenation process for converting an .alpha.,.beta.-olefincially unsaturated carbonylic compound into the corresponding allylic alcohol derivative which comprises reacting and .alpha.,.beta.-olefinically unsaturated carbonylic compound with hydrogen in the vapor phase at a temperature between about 0°C and 300°C and a pressure between about 15 and 15,000 psi in the presence of a catalyst comprising a silver-cadmium alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the alloy exhibits and X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines.
Acrolein is hydrogenated to allylic alcohol at high conversions and high yields.
Description
~(~87sg7 ; :~:
BACKGROUND OF TNE INVENTION
Several methods are known in the pTior art for converting a,B-olefinically unsaturated carbonylic compounds into the corresponding ;~
~,B-olefinically unsaturated alcohols.
British 734,247 and U S~ 2,763,696 disclose a process whereby acrolein may be converted to allyl alcohol by means of a vapor phase hydrogenation process. AccoTding to this process, moderate yields of allyl alcohol are obtained when acrolein is treated with free hydrogen in the vapor phase at a temperature between 210C and 240C in the presence of a catalyst comprising cadmium and one or more heavy metals of groups ~, II, VI and VIII of the poriodlc table. Relatively high pressures are oll~loyed in the process on the order o~ 20 to 50 kilograms por square centimeter~
German Patent 858,247 discloses a somewhat diffeTent process which is also useful for the conversion of acrolein ~o allyl alcohol.
According to the German patent, good yields of ~
: `.
... , ., ... :
37S9~ f allyl alcohol are obtained by reacting acrolein with free hydrogen in the presence of a catalyst containing cadmium oxide and a I metal hydrogenating component which is preferably copper. The ¦ patent teaches that the best results are obtained when the ! ;~
process is operated at high temperaturles and at high pressures on the order of 100-300 atmospheres.
I It is also known to convert ~,~-unsaturated aldehydes ¦l into the corresponding unsaturated alcohols in the liquid phase by~
means of hydrogenation in the presence o~ a mixtuxe of a copper f ! soap and a cadmium soap. It is assumed that the copper salt i8 the catalyst and that the cadmium salt only servss the function , of preventing the copper salt from being reduced 1:o metallic i' copper. The use of a solution of a mixture of a copper salt and 1, a cadmium salt for catalyst has the disadvantage that the ~ystem is extremely unstable under the re~uired processing conditions, ' and fluctuations in conditions can cause reduction o~ the Cd2+
salt and/or the CU2+ salt to metals.
U.S. 3,686,333 describes a liquid phase hydrogenation , process for converting alkenals into alkenols in the presence of Ij a catalyst mixture of a cadmium sal~ of a fatty acid and a ;~
" transition metal salt o~ a fatty acid. ¦
;j Japanese Patent 73-01,361 discloses a process ~or i hydrogenating , ~olefi~ically unsaturated aldehydes into the ; corresponding allylic alcohol derivatives. The efficiency of the j f process is improved by the recycle o~ by-product6 to the ¦ hydrogenation zone, or by passage of the by-products stream into ¦ a second hydrogenation zone. ~I~he preferred catalyE;ts are ! mixtures of cadmium and copper, cadmium and silver~ cadmium and ., - 2 -~o~ i~s~
zinc, cadmium and chromiumJ copper and chromium, and the like. The Japanese patent states that under steady state conditions 1.5 moles/hour ' of acrolein are converted to 1.05 moles/hour of allyl alcohol and 0.4 mole/hour of n~propanol.
There remains a need for a co~mercially feasible vapor phase process for converting a,~-olefinically unsaturated carbonylic compounds into allylic derivatives in higher efficiency and yield than has been achieved heretofore in the prior art. ~;
Accordingly, it would be advantageous to have an improved process oT producing allylic alcohol derivatives by hydrogenation of a,B_olefinically un~aturated carbonylic compounds; e.g. a process for converting acrolein into allyl alcohol with a conversion of at least 95 porcen~ and a yield of at laast 7a percent, It woul~ also be advanta~eous to have a novel silver-cadmlum alloy and silver.cadmium~zinc alloy catalysts for selective hydrogenation of ,B-olef~nically unsaturated carbonylic compound to the corresponding allylic alcohol derivatives, .,, ) -3-:.:. j ' , : : , . . .
- lO~S~
DESCRIPTION OF T~IE INVENTION
..... . ~ ` .
The present invention provides an improved hydrogenation process for converting an a,~-olefinically unsaturated carbonylic compound into the corresponding allylic alcohol derivative which comprises reacting an a,~
olefinically unsaturated carbonylic compound with hydrogen in the vapor phase at a temperature between about 0C and 300C and a pressure between about 15 and 15,000 psi in the presence of a catalyst comprising a silver-cadmium alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the alloy exhibits an X-ray diffraction pattern which is substantially free of ;~
detectable unalloyed metal crystallite lines. ;~
The present invention further provides an improved hydrogenation process for convcrting an a,~-olefinically unsaturated carbonylic compound Lnto the correspon~ing allylic alcohol derivative which comprises reacting an a,~-olefinically unsaturate-l carbonylic compound with hydrogen in the vapor phase at a temperature between about 0C and 300C and a pressure be-tween about 15 and 15JOOO psi in the presence of a catalyst comprising a silver-cadmium-zinc alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to -;~
1 and the zinc is contained ~ thec~loy in a quantity between about 0.001 and 30 weight percent, based on the total weight of alloy, and wherein the silver-cadmi~lm-zinc alloy exhibits an X-ray diffraction pattern which is substan-tially free of detectable unalloyed metal crystallite lines.
The a,~-olefinically unsaturated carbonylic compounds amenable to ;~;
the present invention process include those which correspond to the formula~
R R ~ ~
R- C =C- C -R ;~ I;
:-. . ....
wherein R is a substituent selected from h~drogen and hydrocarbon radicals ~ `
containing between one and about 10 carbon atoms. A preferred ciass of aJ~-olefinically unsaturated compounds corresponding to the ab~ve formula are those in which R is a substituent selected from hydrogen and alkyl groups containing between one and about four carbon atoms. ;
~', . ~. :. '.
108759~7 ~
i Illustrative of I,B-olefinically un6aturated compounds which can be selectively hydr~genated ln accordance with the jj invention process are acrolein, methacrolein, crotonaldehyde, ¦¦ tiglic aldehyde, a-ethylacrolein, cinnamaldehyde, 2-hexenal, methylvinyl ketone, methylisopropenyl ketone, ethylvinyl ketone, cyclohexenylisopropenyl ketone, and the like. Heteroatoms such , as halogen and nitrogen may also be present in the compounds being ~electively hydrogenated to allylic derivatives.
In the practice of the invention proces~, the a,~- I
olefinically unsaturated carbonylic compound and hydrogen at ¦~
elevated temperature and pressure are passed in vapor pha~e through a reaction zone containing a novel silver-cadmium alloy or silver-cadmium-zinc alloy catalyst having exceptional selective I hydrogenation activity.
!The reaction temperature of the hydrogenation process can vary in the range between about 0C and 300C, and preferably ¦
between about 75C and 250C~ and most preferably between about 100C and 215C.
The pressure of the hydrogenation proaess can vary in the range between about 15 and 15,000 psi, and preferably betwéen about 75 and 5000 pgi, and most preferably between about 250 and !' 2500 psi. I -i The mole ratio of hydrogen to ~ ole~inically 1 unsaturated carbonylic compound in the vapor phase feed stream j can vary in the range between about i:l and 1000:1. For the , ~elective hydrogenation of an aldehydic compound such as acrolein, the preferred mole ratio of hydrogen to carbonylic compound in the feed gtream is in the range between zlbout 5:1 ¦
. I
, 5 .1 , . !
and 200:1~ and the ~ost preferred mole ratio in the range between about 10:1 and 150:1.
!~ The rate at which the vapor phase gas stream is l! contacted with the silver-cadmium alloy or silver-cadmium-zinc ¦¦ alloy catalyst is no~ critical, and can be varied consonant with the other processing conditions to achieve an optimal i balance of conversion and yield param~ters. The flow rate of feed gas reactants can vary over a broad range between about a ~! total of 10 moles and 1000 moles of feed gas reactants per liter o~ catalyst per hour. In the case o acrolein and methylvinyl ketone and other low molecular weight carbonylic compound~, a preferred flow rate of feed gas reactants is one which provides ~ a catalyst contact time between about 0.1 and 50 second~. By ¦ -I the invention process, acrolein can be converted to allyl alcohol !:
with a space-time yield of greater than 900 grams per liter of catalyst per hour.
The process can be conducted either by passing the feed mixture through a fixed catalyst bed, or through a reactor wherein the catalyst i8 present in finely divided form and is maintained in a fluidized state by the upward passage there- ¦
through of the gaseous reactants. The process is most conveniently carried out in a continuous manner, although ~ ¦
intermittent types of operation can be employed. In a preferred ¦
method of continuous operation, the components of the feed ¦
j stream are brought together and under the desired pressure are passed in a vapor phase through the catalyst heate~S to the desire~ temperature. The reac~ion zone advantageously is an elongated tube or tubes containing the catalyst~ ~hls feed can be ' I ~
, - 6 -,. ~', ,,. ~ r~
` ~87S9r7 brought into contact with the catalyst in either the unheated or preheated condition. l~e ef~luent from the reactor can then be separated into its various constituents by conventional means, the most convenient of which is of fractional distillation. If desired, any unconverted portion of the carbonylic reactant present in the effluent can be recirculated through the catalyst in the reactor~ preferably admixed wi~h fresh feed gases.
CATALYST PREPARATION
The present invention in another aspect provides a catalyst compo- -~
sition consisting essentially of a silver-cadmium alloy on a carrier sub-strate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1; and wherein the silver-cadmium alloy exhibits an X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines. ~-The present invention further provides a catalyst composition consisting ossontially of a silver-cadmium-zinc alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the ran~e of between about 0.1 and 3 to 1, and the zinc is contained in the alloy in a `
quantity between about 0.001 and 30 weight percent> based on the total ;~
weight of alloy; and wherein the silver-cadmium-zinc alloy exhibits an X-ray diffraction pattern which is substantially free of detectable un-alloyed metal crystallite lines.
The carrier substrate can be selected from silica, Celite, diatomaceous earth, Kieselguhr, alumina, silica-alumina, titanium oxide, pumic, carborundum, boria, and the like. It is highly preferred that the silver-cadmium alloy be supported on a silica and/or ~alumina carrier substrate. The quantity of carrier substrate in the catalyst composition can vary in the range of between about 5 and 99.5 weight percent, based on the total catalyst weight.
, ~.'':
- 7 - ~ ;~
1`~875~
1:
.
~ i !' ! ~
The preferred catalysts are prepared by coprecipitating I hydr~xides of silver and cadmium or silver, cadmium and zinc " from an aqueous solution of calculated ~uantities of water-il soluble salts of the metals. The precipitation is leffected by ¦
! the addition of caustic to the aqueous solution. Preferably, , the finely divided carrier substrate mass is slurried in the said aqueous medium immediately after the silver-cadmium or silver-cadmium-zinc hydroxides are precipitated. F.lnely divided porous materials ~uch as fumed silica ox diatomaceous earth are ~ highly preferred carrier substrate matexials ~or ~he preparation ! Of the prese~t invention catalysts.
After the coprecipitation of silver-cadmium or the , ;
silver-cadmium-zinc hydroxides has been accomplished, the solids phase is recovered by filtration or other conventional means.
jl The filtered solids are washed with chlorine-free wa*er until ¦
; , .
essentially neutral. For the purposes of a fixed bed operation, the dried filter cake preparation is calcined at a temperature ! :
between about 175C and 300C for a period of abou~ two to ¦
twenty hours cr longer, and then the calcined material is ground and pelleted. Prior to use the catalyst pellets can be reduced in a stream of hydrogen at a temperature between about ¦
50C and 250C for a period of time up to about five hours.
, For a fluidized bed operation, the calcined catalyst preparation ; can be ground and sized in a conventional manner to ~atisfy I, process design requirements. The reduction o~ the catalyst can ¦ j jl also be accomplished in ~itu during a vapor phase hyclrogenation il proce~s.
., . I
.'~ I
!! I
! i ~
, ~87S~7 1:
j, I
There are several critlcal aspects of catalyst prepara-tion which must be respected in order to achieve a novel type of ¦
' hydrogenation catalyst having unique ~nd advantageous properties !l in comparison to prior art catalysts for selec~ive hydrogenation ¦
! of acrolein type compounds to allyl alcohol type compounds.
Firstly, in a silver-cadmium alloy catalyst the silver-'I cadmium alloy must contain an atomic ratio of silver to cadmiumin the range between about 0.1 and 3 to 1, and preferably I! between about 0.4 and 2.2 to 1. In a ~ilver-caclmium-zinc alloy catalyst, the silver-cadmium-zina alloy must contain an atomic ratio of silver to cadmium in the range between about 0.1 and i 3 to 1, and preferably between about 0.4 and 2.2 to 1; and the ., silver-cadmium-zinc alloy must contain between about 0.001 and .
30 weight percent zinc, and preferably between about 0.01 and 15 weight percent zincl based on the totai weight of alloy.
Secondly, the silver, cadmium and zinc in the catalysts must be in the free metal ~tate, and must be substantially in the ~orm of an alloy, i.e., X-ray diffraction ~pectra should . confirm the absence of unalloyed silver, cadmlum or zinc crystals~ Preferred silver-cadmium and silver-cadmium-zinc alloy ,; catalysts are solid solutions which nominally exhibit:an X-ray . diffraction pattern whi.ch is substantially free of~detectable ~ :
unalloyed metal crystallite lines.
,! In terms ~f X-r~y diffraction data as more fully !¦ described hereinbelow, a preferred alloy catalyst can consis~
~, substantially o~ a-phase gilver-cadmium or silver-cadmium-zinc, without detectable zplitting of X-ray diffraction lines wbich is .. indicative o~ ~lver-rich and/or cadmium-rlch and~'or zinc-rich .
_ g I
j 1~87S9~
~ . t -phase crystallites. Silver-cadmium and silver-cadmium-zinc alloy catalysts which also have outstalnding selectivity for ii high yield conversion of acrolein-type compounds into allyl ¦¦ alcohol-type compo~ncts are those in whi~h the alloy composition j !I consists of more than-about 50 percent of ~-phase silver-cadmium ¦
- t or silver-cadmium-zinc crystallites as characterized by X-ray ; diffraction pattern. I
'I Other preferred silver-cadmium alloy and silver-!l cadmium-zinc alloy catalysts can have a,y and E-phase crystallites pregent. Those especially rich in E-phase, while highly selective, are somewhat less active than those richer in ¦
nonsplit -pha~e alloy.
Thirdly, it has been found that the production o~
silver-cadmium alloy and silver-cadmium-zinc alloy catalysts, I which exhibit the greatest selectivity for converting bcrolein ¦
to allyl alcohol, can be achieved if the coprecipitation step of the catalyst preparation is conducted within restricted limitations and under controlled conditions. Thus, the total , concentration o~ the water-soluble salts (e.g., nitrate salts) ¦ in the aqueous solution ~hould be maintained in the range between¦
about 5 weight percent, and the ~olubiIity limit of the salts, and the quantity of caustic added as a precipitating agent should approximate the stoichiometric a unt within narrow limits.
It is particularly ~dvantageous to employ ~ water-soluble hydroxide (e.g., an alkali metal hydroxide~ ~s the caustic l precipitating agent, and to add the caustic rapidly with '! ~tirring to facilitate formation of a precipit~te of fine ; crystals. Excellent results are obtained, ~or example, if 17 grams of ~ilver ni~xate and 34 grams of cactmi~m nitrate are :, ~
'!
1087`59~
dissolved in 200 milliliters of water, and 18 grams o~ potassium ~! hydroxide are dissolved in 200 milliliters of water, and both ¦~ solutions are added simultaneously to l00 milliliters of water ¦ with rapid stirring.
~, Other precautions must be oblserved during catalyst t preparation if highly selective silver-cadmium and silver-~ cadmium-zinc alloy compositions are to be achieved. It has ¦
;! been found that the calcination step of the catalyst preparation ¦I most advantageously must be conducted within narrowly controlled limitations. The calcination step ~hould be accomplished at a temperature between about ~75C and 300C, and most pre~erably ~ at a temperature between about 200C and 2~0C. ~ calcination ! of a silver-cadmium or silver-cadmium-zinc alloy~catal~st is :
, conducted at a temperature above about 300C, the r~sultant catalyst exhibits lesg selectivity $or high yield conversion of acrolein to allyl alcohol in a vapor phase process.
! ' .
The importance o~' controlled calcination conditions is ~, apparent from a comparison of the data presented in the Examples hereinbelow with the data reported in Example`VII of U~S.
BACKGROUND OF TNE INVENTION
Several methods are known in the pTior art for converting a,B-olefinically unsaturated carbonylic compounds into the corresponding ;~
~,B-olefinically unsaturated alcohols.
British 734,247 and U S~ 2,763,696 disclose a process whereby acrolein may be converted to allyl alcohol by means of a vapor phase hydrogenation process. AccoTding to this process, moderate yields of allyl alcohol are obtained when acrolein is treated with free hydrogen in the vapor phase at a temperature between 210C and 240C in the presence of a catalyst comprising cadmium and one or more heavy metals of groups ~, II, VI and VIII of the poriodlc table. Relatively high pressures are oll~loyed in the process on the order o~ 20 to 50 kilograms por square centimeter~
German Patent 858,247 discloses a somewhat diffeTent process which is also useful for the conversion of acrolein ~o allyl alcohol.
According to the German patent, good yields of ~
: `.
... , ., ... :
37S9~ f allyl alcohol are obtained by reacting acrolein with free hydrogen in the presence of a catalyst containing cadmium oxide and a I metal hydrogenating component which is preferably copper. The ¦ patent teaches that the best results are obtained when the ! ;~
process is operated at high temperaturles and at high pressures on the order of 100-300 atmospheres.
I It is also known to convert ~,~-unsaturated aldehydes ¦l into the corresponding unsaturated alcohols in the liquid phase by~
means of hydrogenation in the presence o~ a mixtuxe of a copper f ! soap and a cadmium soap. It is assumed that the copper salt i8 the catalyst and that the cadmium salt only servss the function , of preventing the copper salt from being reduced 1:o metallic i' copper. The use of a solution of a mixture of a copper salt and 1, a cadmium salt for catalyst has the disadvantage that the ~ystem is extremely unstable under the re~uired processing conditions, ' and fluctuations in conditions can cause reduction o~ the Cd2+
salt and/or the CU2+ salt to metals.
U.S. 3,686,333 describes a liquid phase hydrogenation , process for converting alkenals into alkenols in the presence of Ij a catalyst mixture of a cadmium sal~ of a fatty acid and a ;~
" transition metal salt o~ a fatty acid. ¦
;j Japanese Patent 73-01,361 discloses a process ~or i hydrogenating , ~olefi~ically unsaturated aldehydes into the ; corresponding allylic alcohol derivatives. The efficiency of the j f process is improved by the recycle o~ by-product6 to the ¦ hydrogenation zone, or by passage of the by-products stream into ¦ a second hydrogenation zone. ~I~he preferred catalyE;ts are ! mixtures of cadmium and copper, cadmium and silver~ cadmium and ., - 2 -~o~ i~s~
zinc, cadmium and chromiumJ copper and chromium, and the like. The Japanese patent states that under steady state conditions 1.5 moles/hour ' of acrolein are converted to 1.05 moles/hour of allyl alcohol and 0.4 mole/hour of n~propanol.
There remains a need for a co~mercially feasible vapor phase process for converting a,~-olefinically unsaturated carbonylic compounds into allylic derivatives in higher efficiency and yield than has been achieved heretofore in the prior art. ~;
Accordingly, it would be advantageous to have an improved process oT producing allylic alcohol derivatives by hydrogenation of a,B_olefinically un~aturated carbonylic compounds; e.g. a process for converting acrolein into allyl alcohol with a conversion of at least 95 porcen~ and a yield of at laast 7a percent, It woul~ also be advanta~eous to have a novel silver-cadmlum alloy and silver.cadmium~zinc alloy catalysts for selective hydrogenation of ,B-olef~nically unsaturated carbonylic compound to the corresponding allylic alcohol derivatives, .,, ) -3-:.:. j ' , : : , . . .
- lO~S~
DESCRIPTION OF T~IE INVENTION
..... . ~ ` .
The present invention provides an improved hydrogenation process for converting an a,~-olefinically unsaturated carbonylic compound into the corresponding allylic alcohol derivative which comprises reacting an a,~
olefinically unsaturated carbonylic compound with hydrogen in the vapor phase at a temperature between about 0C and 300C and a pressure between about 15 and 15,000 psi in the presence of a catalyst comprising a silver-cadmium alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the alloy exhibits an X-ray diffraction pattern which is substantially free of ;~
detectable unalloyed metal crystallite lines. ;~
The present invention further provides an improved hydrogenation process for convcrting an a,~-olefinically unsaturated carbonylic compound Lnto the correspon~ing allylic alcohol derivative which comprises reacting an a,~-olefinically unsaturate-l carbonylic compound with hydrogen in the vapor phase at a temperature between about 0C and 300C and a pressure be-tween about 15 and 15JOOO psi in the presence of a catalyst comprising a silver-cadmium-zinc alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to -;~
1 and the zinc is contained ~ thec~loy in a quantity between about 0.001 and 30 weight percent, based on the total weight of alloy, and wherein the silver-cadmi~lm-zinc alloy exhibits an X-ray diffraction pattern which is substan-tially free of detectable unalloyed metal crystallite lines.
The a,~-olefinically unsaturated carbonylic compounds amenable to ;~;
the present invention process include those which correspond to the formula~
R R ~ ~
R- C =C- C -R ;~ I;
:-. . ....
wherein R is a substituent selected from h~drogen and hydrocarbon radicals ~ `
containing between one and about 10 carbon atoms. A preferred ciass of aJ~-olefinically unsaturated compounds corresponding to the ab~ve formula are those in which R is a substituent selected from hydrogen and alkyl groups containing between one and about four carbon atoms. ;
~', . ~. :. '.
108759~7 ~
i Illustrative of I,B-olefinically un6aturated compounds which can be selectively hydr~genated ln accordance with the jj invention process are acrolein, methacrolein, crotonaldehyde, ¦¦ tiglic aldehyde, a-ethylacrolein, cinnamaldehyde, 2-hexenal, methylvinyl ketone, methylisopropenyl ketone, ethylvinyl ketone, cyclohexenylisopropenyl ketone, and the like. Heteroatoms such , as halogen and nitrogen may also be present in the compounds being ~electively hydrogenated to allylic derivatives.
In the practice of the invention proces~, the a,~- I
olefinically unsaturated carbonylic compound and hydrogen at ¦~
elevated temperature and pressure are passed in vapor pha~e through a reaction zone containing a novel silver-cadmium alloy or silver-cadmium-zinc alloy catalyst having exceptional selective I hydrogenation activity.
!The reaction temperature of the hydrogenation process can vary in the range between about 0C and 300C, and preferably ¦
between about 75C and 250C~ and most preferably between about 100C and 215C.
The pressure of the hydrogenation proaess can vary in the range between about 15 and 15,000 psi, and preferably betwéen about 75 and 5000 pgi, and most preferably between about 250 and !' 2500 psi. I -i The mole ratio of hydrogen to ~ ole~inically 1 unsaturated carbonylic compound in the vapor phase feed stream j can vary in the range between about i:l and 1000:1. For the , ~elective hydrogenation of an aldehydic compound such as acrolein, the preferred mole ratio of hydrogen to carbonylic compound in the feed gtream is in the range between zlbout 5:1 ¦
. I
, 5 .1 , . !
and 200:1~ and the ~ost preferred mole ratio in the range between about 10:1 and 150:1.
!~ The rate at which the vapor phase gas stream is l! contacted with the silver-cadmium alloy or silver-cadmium-zinc ¦¦ alloy catalyst is no~ critical, and can be varied consonant with the other processing conditions to achieve an optimal i balance of conversion and yield param~ters. The flow rate of feed gas reactants can vary over a broad range between about a ~! total of 10 moles and 1000 moles of feed gas reactants per liter o~ catalyst per hour. In the case o acrolein and methylvinyl ketone and other low molecular weight carbonylic compound~, a preferred flow rate of feed gas reactants is one which provides ~ a catalyst contact time between about 0.1 and 50 second~. By ¦ -I the invention process, acrolein can be converted to allyl alcohol !:
with a space-time yield of greater than 900 grams per liter of catalyst per hour.
The process can be conducted either by passing the feed mixture through a fixed catalyst bed, or through a reactor wherein the catalyst i8 present in finely divided form and is maintained in a fluidized state by the upward passage there- ¦
through of the gaseous reactants. The process is most conveniently carried out in a continuous manner, although ~ ¦
intermittent types of operation can be employed. In a preferred ¦
method of continuous operation, the components of the feed ¦
j stream are brought together and under the desired pressure are passed in a vapor phase through the catalyst heate~S to the desire~ temperature. The reac~ion zone advantageously is an elongated tube or tubes containing the catalyst~ ~hls feed can be ' I ~
, - 6 -,. ~', ,,. ~ r~
` ~87S9r7 brought into contact with the catalyst in either the unheated or preheated condition. l~e ef~luent from the reactor can then be separated into its various constituents by conventional means, the most convenient of which is of fractional distillation. If desired, any unconverted portion of the carbonylic reactant present in the effluent can be recirculated through the catalyst in the reactor~ preferably admixed wi~h fresh feed gases.
CATALYST PREPARATION
The present invention in another aspect provides a catalyst compo- -~
sition consisting essentially of a silver-cadmium alloy on a carrier sub-strate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1; and wherein the silver-cadmium alloy exhibits an X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines. ~-The present invention further provides a catalyst composition consisting ossontially of a silver-cadmium-zinc alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the ran~e of between about 0.1 and 3 to 1, and the zinc is contained in the alloy in a `
quantity between about 0.001 and 30 weight percent> based on the total ;~
weight of alloy; and wherein the silver-cadmium-zinc alloy exhibits an X-ray diffraction pattern which is substantially free of detectable un-alloyed metal crystallite lines.
The carrier substrate can be selected from silica, Celite, diatomaceous earth, Kieselguhr, alumina, silica-alumina, titanium oxide, pumic, carborundum, boria, and the like. It is highly preferred that the silver-cadmium alloy be supported on a silica and/or ~alumina carrier substrate. The quantity of carrier substrate in the catalyst composition can vary in the range of between about 5 and 99.5 weight percent, based on the total catalyst weight.
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The preferred catalysts are prepared by coprecipitating I hydr~xides of silver and cadmium or silver, cadmium and zinc " from an aqueous solution of calculated ~uantities of water-il soluble salts of the metals. The precipitation is leffected by ¦
! the addition of caustic to the aqueous solution. Preferably, , the finely divided carrier substrate mass is slurried in the said aqueous medium immediately after the silver-cadmium or silver-cadmium-zinc hydroxides are precipitated. F.lnely divided porous materials ~uch as fumed silica ox diatomaceous earth are ~ highly preferred carrier substrate matexials ~or ~he preparation ! Of the prese~t invention catalysts.
After the coprecipitation of silver-cadmium or the , ;
silver-cadmium-zinc hydroxides has been accomplished, the solids phase is recovered by filtration or other conventional means.
jl The filtered solids are washed with chlorine-free wa*er until ¦
; , .
essentially neutral. For the purposes of a fixed bed operation, the dried filter cake preparation is calcined at a temperature ! :
between about 175C and 300C for a period of abou~ two to ¦
twenty hours cr longer, and then the calcined material is ground and pelleted. Prior to use the catalyst pellets can be reduced in a stream of hydrogen at a temperature between about ¦
50C and 250C for a period of time up to about five hours.
, For a fluidized bed operation, the calcined catalyst preparation ; can be ground and sized in a conventional manner to ~atisfy I, process design requirements. The reduction o~ the catalyst can ¦ j jl also be accomplished in ~itu during a vapor phase hyclrogenation il proce~s.
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There are several critlcal aspects of catalyst prepara-tion which must be respected in order to achieve a novel type of ¦
' hydrogenation catalyst having unique ~nd advantageous properties !l in comparison to prior art catalysts for selec~ive hydrogenation ¦
! of acrolein type compounds to allyl alcohol type compounds.
Firstly, in a silver-cadmium alloy catalyst the silver-'I cadmium alloy must contain an atomic ratio of silver to cadmiumin the range between about 0.1 and 3 to 1, and preferably I! between about 0.4 and 2.2 to 1. In a ~ilver-caclmium-zinc alloy catalyst, the silver-cadmium-zina alloy must contain an atomic ratio of silver to cadmium in the range between about 0.1 and i 3 to 1, and preferably between about 0.4 and 2.2 to 1; and the ., silver-cadmium-zinc alloy must contain between about 0.001 and .
30 weight percent zinc, and preferably between about 0.01 and 15 weight percent zincl based on the totai weight of alloy.
Secondly, the silver, cadmium and zinc in the catalysts must be in the free metal ~tate, and must be substantially in the ~orm of an alloy, i.e., X-ray diffraction ~pectra should . confirm the absence of unalloyed silver, cadmlum or zinc crystals~ Preferred silver-cadmium and silver-cadmium-zinc alloy ,; catalysts are solid solutions which nominally exhibit:an X-ray . diffraction pattern whi.ch is substantially free of~detectable ~ :
unalloyed metal crystallite lines.
,! In terms ~f X-r~y diffraction data as more fully !¦ described hereinbelow, a preferred alloy catalyst can consis~
~, substantially o~ a-phase gilver-cadmium or silver-cadmium-zinc, without detectable zplitting of X-ray diffraction lines wbich is .. indicative o~ ~lver-rich and/or cadmium-rlch and~'or zinc-rich .
_ g I
j 1~87S9~
~ . t -phase crystallites. Silver-cadmium and silver-cadmium-zinc alloy catalysts which also have outstalnding selectivity for ii high yield conversion of acrolein-type compounds into allyl ¦¦ alcohol-type compo~ncts are those in whi~h the alloy composition j !I consists of more than-about 50 percent of ~-phase silver-cadmium ¦
- t or silver-cadmium-zinc crystallites as characterized by X-ray ; diffraction pattern. I
'I Other preferred silver-cadmium alloy and silver-!l cadmium-zinc alloy catalysts can have a,y and E-phase crystallites pregent. Those especially rich in E-phase, while highly selective, are somewhat less active than those richer in ¦
nonsplit -pha~e alloy.
Thirdly, it has been found that the production o~
silver-cadmium alloy and silver-cadmium-zinc alloy catalysts, I which exhibit the greatest selectivity for converting bcrolein ¦
to allyl alcohol, can be achieved if the coprecipitation step of the catalyst preparation is conducted within restricted limitations and under controlled conditions. Thus, the total , concentration o~ the water-soluble salts (e.g., nitrate salts) ¦ in the aqueous solution ~hould be maintained in the range between¦
about 5 weight percent, and the ~olubiIity limit of the salts, and the quantity of caustic added as a precipitating agent should approximate the stoichiometric a unt within narrow limits.
It is particularly ~dvantageous to employ ~ water-soluble hydroxide (e.g., an alkali metal hydroxide~ ~s the caustic l precipitating agent, and to add the caustic rapidly with '! ~tirring to facilitate formation of a precipit~te of fine ; crystals. Excellent results are obtained, ~or example, if 17 grams of ~ilver ni~xate and 34 grams of cactmi~m nitrate are :, ~
'!
1087`59~
dissolved in 200 milliliters of water, and 18 grams o~ potassium ~! hydroxide are dissolved in 200 milliliters of water, and both ¦~ solutions are added simultaneously to l00 milliliters of water ¦ with rapid stirring.
~, Other precautions must be oblserved during catalyst t preparation if highly selective silver-cadmium and silver-~ cadmium-zinc alloy compositions are to be achieved. It has ¦
;! been found that the calcination step of the catalyst preparation ¦I most advantageously must be conducted within narrowly controlled limitations. The calcination step ~hould be accomplished at a temperature between about ~75C and 300C, and most pre~erably ~ at a temperature between about 200C and 2~0C. ~ calcination ! of a silver-cadmium or silver-cadmium-zinc alloy~catal~st is :
, conducted at a temperature above about 300C, the r~sultant catalyst exhibits lesg selectivity $or high yield conversion of acrolein to allyl alcohol in a vapor phase process.
! ' .
The importance o~' controlled calcination conditions is ~, apparent from a comparison of the data presented in the Examples hereinbelow with the data reported in Example`VII of U~S.
2,763,696. In the ~aid patent Example VII, over a silver~ I
cadmium catalyst acrolein ig hydrogenated ~n vapor phase~to allyl alcohol in a yield of 38.3% at a conver9ion rate of~9S%. ;
! This ~s in contrast to the results reported hereinbelow. In j;~
~' Example I, inter al~a, acrolein is converted to allyl alcohol l~ in yields above 70~ at a conversion~rate above 95%. The low ! selectivity of the UiS 2,763,696 catalyst ~s b~lieved to be I! attributable to ~he pre5ence of a substantial quantity o~
I unalloyed silver crystallites. The patent oatalyst is calcined ~' I
~0875~7 ` ~:
~t 400C or Z-6 hours during the preparation proceduTe. High calcination temperatures can have the effect of SegTegating the active metal species into large crystallites of unalloyed silver and unalloyed cadmium. The presence of unalloyed silver ~md/or cadmium is detrimental to the hydro~
genation selectivity properties of silver-cadmium catalysts.
It has also been found that the silver-cadmium alloy and --silver-cadmium-zinc alloy catalysts of the present invention are most ef~ective when supported on a carrier substrate, i.e., in combination with an internal diluent Catalysts prepared without a carrier substrate have been found to have a lower activity and shorter catalyst life than the corresponding supported catalysts in vapor phase hydrogenation processes. ~ ~;
A typical carrier substrate will have an initial surface aTea oE more than about 1-10 m2/gm, and an average pore diameter greater than about 20 a. A high proport~on of smnll pores is detrimental to catalyst activity, i thc slze of the pores ar~ such that caplllary condensation o~ an acrolein-type compound occurs and causes pore blockage. This results in loss of catalytic activity, The following examples are further illustrative of the present invention. The reactants and other specific ingredients are presen~ed as being typical, and various modifications can be derived in view of ;~
the oregoing disclosure within the scope of the invention.
The X~ray difraction photographs were obtained on a Rhilips*
XRG~3000 constant potential, constant milliampere X-ray generator, using Ni filtered CuKa radiation~ 35 KV and 20 MA~ The diffraction *Trademark ' .
~12 :1~87~g7 ~ ~
photographs were prepared from the catalyst samples after a slight ~ortar treatment using Philips Debye-Scherrer* Powder Cameras of 114.6 mm diameter, ~ith 0~3 ~m diameter thin walled glass capillaries for the samples and a film illuminator and measuring device for measurement of the diffraction ;~ ~ ;
lines. Ilord industrial X-ray film type G was used for the photographs.
The X-ray diffraction identification of Ag, CdO and AgCd is in accordance with Astrand and Westgreen Z. anorg. Allg. Chemic, 175, 90 (1928), The crystal planes are 111, 200, 220, 311, etc. Phase diagrams of AgCd, AgZn, CdZn, and the like, are published in "Constitution of Binary Alloy~" by Max Hansen t2nd Edition, McGraw Hill~ New York, N.Y.
1958~, ''''.' :
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Ag 2.36(100), 2.04(38), 1.445(25), 1.23~26), 1.18~13).
-AgCd Values are usually ~lightly higher than Ag . o ' to 2.41A etc. The slight changes in spacing ¦, are quite visible visually, especially when I the back reflection scattering can ~lso be " seen, i.e., 2.36 to 2.41 A for 111.
;. o y-AgCd aO from 9.935 to 9.982 A is a complex body centered sy~tem, thus calculation yields the spacing ranges. The spacings actually are quite close to those of Ag. 2.:34-Z.35, 2.03-2.04, 1.43-1.44, 1.23, 1.~8-1.1~ A; however there are spacings at 1.66-1.67 ~Ind 1.35-1.36 A
which are not presented in Ag.
~-AgCd aO from 3.040 to 3.095 A, cO const~t 4.810 A, j hexagonal system. With E-AgCd essenti~lly every ¦
;~ line visible in the spectra can be ~overed. !
; There is a distinction however, i.eO, spacings , o , at 2.65, 2.41, 2.31 A allow distinction from i! !
I Ag and y-AgCd.
CdO 2.71(100), 2.35(83), 1.66~43), 1.42(28), 1.36~13), 1.05~13), 0.96 :
j' '.! j - 13a -', I
Il I ,.~, 10~759~
EXAMPLE I
A catalyst was prepared by the rapid dTopwise co~addi~ion of laO milliliters of a 1.0 molar AgN03, 0.49 molar CdtN03)2 solution and 100 milliliters of a 1,72 molar KOH solution to 400 milliliters of ~
vigorously stirred doubly distilled water. About lSI grams of Cab-O-Sil* ~ -Hs5 silica ~325 m2/g, Cabot Corp~ Boston, Mass. a fumed silica) were then thoxoughly mixed with the resultant slurry of silYer-cadmium coprecipitate. ;i The slurry was filtered, and the filter cake was washed with about 600 milliliters of doubly distilled water. The filter cake was calcined in -air at 250C or 16 houTs, The Tesultant material was crushed and screened to yield a 50-80 mesh fraction. Bulk chemical analysis of this matesial indicated that it contalned 54~ SiO2, 17.3% Cd, 27,5~ Ag with 0.3~ K
also pres~nt. Powder X-ray diffraction studlcs revealed that the com-~oaition metallic silver crystallit0s nnd c~dmium oxyhydroxld~ Cd3LO~OH)]2 of two types, and cadmium hydroxide Cd~OH)2, The silica, being amorFhous, contributed no significant X-ray diffraction pattern.
Approximately 2.62 grams of the prepared silver-cadmium catalyst was charged to a 0,925 cm i,d. by 28 cm reactor tube. HydTogen gas a~
200 psig was passed over the catalyst in the reactor tube at 500 SCCM and the temperature was increased from 21C to 175C over the course of one hour, at which time the gas was changed to one containing 1 part acrolein and 40 parts hydrogen. The reactor ~fluent was sampled using a gas ~;
sampling valve and gas chromatography~ Table I summarizes the process conditions employed and the product yields obtained. ~-~
,-,............................................................................................ ..., ~
*Trademark ~ ;
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;~ :
,. Powder X-ray diffraction examination of the used catalyst disclosed lines at 2.38, 2.06, 1.46 and 1.25 A, which indicated , I`
that a silver-cadmium alloy of the a-ty~ was present on the silica.
~Chemical analysis of the alloy determined the content as 61.4%
¦iAg and 38.5% Cd by weight. No discrete Ag or Cd crystallites were detectable.
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', - 16 - i ssq EXAMPLE II ,~
A silver~cadmium solution was prepared by dissolving 34 grams , AgN03 (0.020 mole) and 30 grams Cd(N03~2.4H20 ~0~097 ~ole~ in doubly '~
distilled water to a total solution volume of 200 milliliters. A sodium hyd~oxide solution was prepared by dissolving 11,9 grams of NaOH ~0,298 ~ ~molel in sùfficient doubly distilled water to adjust the volume to 200 ~ ;
milliliters~ Both solutions were then added dropwise with rapid stirring ~ ,' to 400 milliliters of distilled water~ The resultant brown precipitate ,~
was recovered and added to a suspension of lOO millîliters of Cab-O-Sil*
M-5 (a umed silica) in 200 milliliters of distilled water with rapid stirring~ The suspension was filtered, and the filter cake was washed ~ith 2 liters of distilled water~ The moist filter cake was then ~alcined in air ~t 250C for 20 hours~ The material was cooled in a vacuum dcsiccator, and then crushed and screened to yield a 50-80 mesh ractlon which by bulk chemical analysis was found to contain 61~ Ag, 26% Cd and ;~
12~ SiO2~ Powder X~ray diffraction examination indicated that the silver was pTesent as metallic crystallites and the cadmium was present as CdO~
A quantity,of about 7,63 grams of this catalyst precursor was placed in a 0.925 cm i.d. by 28 cm reactor tube and 200 psig hydrogan ;~
flowing at 750 SCCM was passed over the catalyst precursor as the temperature was raised from 23C to 130C over a period of 36 minutes, ;' flt the end of which time the gas was changed to one containing approximately l part acrolein to 40 parts hydrogen~ Table Il summarizes the results ohtained under a ~ariety of procsss conditions with this catalyst.
' ''' *Trademark B
. ~: , . . . . . .
~3875~7 "
X-ray diffraction analysis of the used catalyst exhibited ~trong sharp lines at 2.39, 2.07, 1.46l, and 125 A with a strong, .. relatively sharp, back reflection. This indicated an ~-phase sil~er-cadmium alloy on the silica. The a~erage composition o~ -.i , .
!,~70~ Ag and 30% Cd by weight was determined by chemical analysis.
' No discsete silver or cadmium crystallites cou}d be detected by bulk chemical analysis.
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cadmium catalyst acrolein ig hydrogenated ~n vapor phase~to allyl alcohol in a yield of 38.3% at a conver9ion rate of~9S%. ;
! This ~s in contrast to the results reported hereinbelow. In j;~
~' Example I, inter al~a, acrolein is converted to allyl alcohol l~ in yields above 70~ at a conversion~rate above 95%. The low ! selectivity of the UiS 2,763,696 catalyst ~s b~lieved to be I! attributable to ~he pre5ence of a substantial quantity o~
I unalloyed silver crystallites. The patent oatalyst is calcined ~' I
~0875~7 ` ~:
~t 400C or Z-6 hours during the preparation proceduTe. High calcination temperatures can have the effect of SegTegating the active metal species into large crystallites of unalloyed silver and unalloyed cadmium. The presence of unalloyed silver ~md/or cadmium is detrimental to the hydro~
genation selectivity properties of silver-cadmium catalysts.
It has also been found that the silver-cadmium alloy and --silver-cadmium-zinc alloy catalysts of the present invention are most ef~ective when supported on a carrier substrate, i.e., in combination with an internal diluent Catalysts prepared without a carrier substrate have been found to have a lower activity and shorter catalyst life than the corresponding supported catalysts in vapor phase hydrogenation processes. ~ ~;
A typical carrier substrate will have an initial surface aTea oE more than about 1-10 m2/gm, and an average pore diameter greater than about 20 a. A high proport~on of smnll pores is detrimental to catalyst activity, i thc slze of the pores ar~ such that caplllary condensation o~ an acrolein-type compound occurs and causes pore blockage. This results in loss of catalytic activity, The following examples are further illustrative of the present invention. The reactants and other specific ingredients are presen~ed as being typical, and various modifications can be derived in view of ;~
the oregoing disclosure within the scope of the invention.
The X~ray difraction photographs were obtained on a Rhilips*
XRG~3000 constant potential, constant milliampere X-ray generator, using Ni filtered CuKa radiation~ 35 KV and 20 MA~ The diffraction *Trademark ' .
~12 :1~87~g7 ~ ~
photographs were prepared from the catalyst samples after a slight ~ortar treatment using Philips Debye-Scherrer* Powder Cameras of 114.6 mm diameter, ~ith 0~3 ~m diameter thin walled glass capillaries for the samples and a film illuminator and measuring device for measurement of the diffraction ;~ ~ ;
lines. Ilord industrial X-ray film type G was used for the photographs.
The X-ray diffraction identification of Ag, CdO and AgCd is in accordance with Astrand and Westgreen Z. anorg. Allg. Chemic, 175, 90 (1928), The crystal planes are 111, 200, 220, 311, etc. Phase diagrams of AgCd, AgZn, CdZn, and the like, are published in "Constitution of Binary Alloy~" by Max Hansen t2nd Edition, McGraw Hill~ New York, N.Y.
1958~, ''''.' :
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Ag 2.36(100), 2.04(38), 1.445(25), 1.23~26), 1.18~13).
-AgCd Values are usually ~lightly higher than Ag . o ' to 2.41A etc. The slight changes in spacing ¦, are quite visible visually, especially when I the back reflection scattering can ~lso be " seen, i.e., 2.36 to 2.41 A for 111.
;. o y-AgCd aO from 9.935 to 9.982 A is a complex body centered sy~tem, thus calculation yields the spacing ranges. The spacings actually are quite close to those of Ag. 2.:34-Z.35, 2.03-2.04, 1.43-1.44, 1.23, 1.~8-1.1~ A; however there are spacings at 1.66-1.67 ~Ind 1.35-1.36 A
which are not presented in Ag.
~-AgCd aO from 3.040 to 3.095 A, cO const~t 4.810 A, j hexagonal system. With E-AgCd essenti~lly every ¦
;~ line visible in the spectra can be ~overed. !
; There is a distinction however, i.eO, spacings , o , at 2.65, 2.41, 2.31 A allow distinction from i! !
I Ag and y-AgCd.
CdO 2.71(100), 2.35(83), 1.66~43), 1.42(28), 1.36~13), 1.05~13), 0.96 :
j' '.! j - 13a -', I
Il I ,.~, 10~759~
EXAMPLE I
A catalyst was prepared by the rapid dTopwise co~addi~ion of laO milliliters of a 1.0 molar AgN03, 0.49 molar CdtN03)2 solution and 100 milliliters of a 1,72 molar KOH solution to 400 milliliters of ~
vigorously stirred doubly distilled water. About lSI grams of Cab-O-Sil* ~ -Hs5 silica ~325 m2/g, Cabot Corp~ Boston, Mass. a fumed silica) were then thoxoughly mixed with the resultant slurry of silYer-cadmium coprecipitate. ;i The slurry was filtered, and the filter cake was washed with about 600 milliliters of doubly distilled water. The filter cake was calcined in -air at 250C or 16 houTs, The Tesultant material was crushed and screened to yield a 50-80 mesh fraction. Bulk chemical analysis of this matesial indicated that it contalned 54~ SiO2, 17.3% Cd, 27,5~ Ag with 0.3~ K
also pres~nt. Powder X-ray diffraction studlcs revealed that the com-~oaition metallic silver crystallit0s nnd c~dmium oxyhydroxld~ Cd3LO~OH)]2 of two types, and cadmium hydroxide Cd~OH)2, The silica, being amorFhous, contributed no significant X-ray diffraction pattern.
Approximately 2.62 grams of the prepared silver-cadmium catalyst was charged to a 0,925 cm i,d. by 28 cm reactor tube. HydTogen gas a~
200 psig was passed over the catalyst in the reactor tube at 500 SCCM and the temperature was increased from 21C to 175C over the course of one hour, at which time the gas was changed to one containing 1 part acrolein and 40 parts hydrogen. The reactor ~fluent was sampled using a gas ~;
sampling valve and gas chromatography~ Table I summarizes the process conditions employed and the product yields obtained. ~-~
,-,............................................................................................ ..., ~
*Trademark ~ ;
' .`
, ,," :, ~-~87SY~ :
;~ :
,. Powder X-ray diffraction examination of the used catalyst disclosed lines at 2.38, 2.06, 1.46 and 1.25 A, which indicated , I`
that a silver-cadmium alloy of the a-ty~ was present on the silica.
~Chemical analysis of the alloy determined the content as 61.4%
¦iAg and 38.5% Cd by weight. No discrete Ag or Cd crystallites were detectable.
' .'. I ' '~
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', - 16 - i ssq EXAMPLE II ,~
A silver~cadmium solution was prepared by dissolving 34 grams , AgN03 (0.020 mole) and 30 grams Cd(N03~2.4H20 ~0~097 ~ole~ in doubly '~
distilled water to a total solution volume of 200 milliliters. A sodium hyd~oxide solution was prepared by dissolving 11,9 grams of NaOH ~0,298 ~ ~molel in sùfficient doubly distilled water to adjust the volume to 200 ~ ;
milliliters~ Both solutions were then added dropwise with rapid stirring ~ ,' to 400 milliliters of distilled water~ The resultant brown precipitate ,~
was recovered and added to a suspension of lOO millîliters of Cab-O-Sil*
M-5 (a umed silica) in 200 milliliters of distilled water with rapid stirring~ The suspension was filtered, and the filter cake was washed ~ith 2 liters of distilled water~ The moist filter cake was then ~alcined in air ~t 250C for 20 hours~ The material was cooled in a vacuum dcsiccator, and then crushed and screened to yield a 50-80 mesh ractlon which by bulk chemical analysis was found to contain 61~ Ag, 26% Cd and ;~
12~ SiO2~ Powder X~ray diffraction examination indicated that the silver was pTesent as metallic crystallites and the cadmium was present as CdO~
A quantity,of about 7,63 grams of this catalyst precursor was placed in a 0.925 cm i.d. by 28 cm reactor tube and 200 psig hydrogan ;~
flowing at 750 SCCM was passed over the catalyst precursor as the temperature was raised from 23C to 130C over a period of 36 minutes, ;' flt the end of which time the gas was changed to one containing approximately l part acrolein to 40 parts hydrogen~ Table Il summarizes the results ohtained under a ~ariety of procsss conditions with this catalyst.
' ''' *Trademark B
. ~: , . . . . . .
~3875~7 "
X-ray diffraction analysis of the used catalyst exhibited ~trong sharp lines at 2.39, 2.07, 1.46l, and 125 A with a strong, .. relatively sharp, back reflection. This indicated an ~-phase sil~er-cadmium alloy on the silica. The a~erage composition o~ -.i , .
!,~70~ Ag and 30% Cd by weight was determined by chemical analysis.
' No discsete silver or cadmium crystallites cou}d be detected by bulk chemical analysis.
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For the preparation of a silver-cadmium solution, 34~7 gTams AgNO3 ~0 204 mole~ and 80.0 grams CdCNO3)2~4H2O (0 259 mole) were dissolved in 100 milliliters of distilled water. To this solution was added 17.0 grams of 86~7% KOH (0~263 ~ole) dissolved in 50 milliiliters of distilled water, followed by addition of 400 milliliters of distilled wa~er. l~e ~lurry mixture which formed was added to 400 milliliters of Cab-O-Sil*
M~5 (a fumed silica~ suspended in one liter of distilled water with rapid stirring. The resultant solids were filtered off, partially air dried overnight, and calcined in air at 250C for 16 hours. ~fter cooling in a vacuum desiccator, the material was partially crushed and extracted with distilled water for about 24 hours, then recalcined a~ 250C to 300C
Por 21 hours in air~ The resultant material contained 34~ by w~lght silver, present as metallic crystallites, 17.9% by weight cadmi~m- as cadmiw~
hydxoxide crystallites of two types, and 33% by weight of silica, with less than 0.05% K or Cl.
This material was crushed and screened to yield a 50-80 mesh fraction, 3,16 grams of which were loaded into 0.925 cm i.d, by 28 cm reactor tu~e~ Hydrogen gas at 200 psig was passed over the catalyst at 2Q 750 SCCM and the temperature brought rapidly rom 22C to 127 C; then the gas was chang0d to l part ucrolein in approximately 40 parts hydTogen.
Table III summaTizes the results obtained under various conditions employing this catalyst. The reactoT effluent stream was analyzed by gas chromatographic techniques. Table III summarizes ',''; .":
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the reactor conditions, and the analysis of liquid products trapped at -78~ in a collection vessel down stream rom the reactor. Bulk chemical analysis of ths used cataly~t in coniunction with X-ray diffraction scanning indicated that an tl ~-phase alloy with an average bulk composition of 62.9% silve~
and 37.1% cadmi~m was present. Broad X-ray diffraction lines at 2.36, 2.05, 1.45, and 1.23 A along with broad back reflection lines were observed, which indicated the presence of ~-phase silver-cadmium. No discrete silver or cadmium metallic crystal- !
lites were detected.
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EXAMPLE IV
A solution was prepared by dis~olving 13.07 grams AgN03 (0.077 molel and 37~97 grams Cd~N03)2~4H20 ~0,123 mole) in l00 milliliters o `
distilled water. A second solution was pTepared by d ssol~ing 20.75 grams of 87.4% analytical reagent grade KOH in (0.32 mole) 100 milliliters of distilled water. Both solutions were then rapidly and simultaneously added to a vigorously stirred 100 mîlliliters of distilled water, and ~ ;~
the resulting precipitate was further suspended by the addition of 500 milliliters of distilled WateT After 1 hour of stirring, 1000milliliters of Cab-O.Sil* M-5 (a fumed silica) were added, in addition to sufficient water at intervals to maintain mixture fluidity. The final volum~ was increased to 1800 nilliliters. The p~l of the superna~ant phas~ was 6.5.
V~cuum ~iltration was omployed to produce a iltor ca~o, which was washed with 2000 milliliters of distilled w~ter. The filter cukc was calclned in air at 250 for 25 hours. After cooling in a vacu~m desiccator, the catalyst pTeCurSOr was crushed and screened to yield a 5d-80 mesh ~raction.
Bulk chemical analysis indicated that the catalyst contained 63.7% SiO2~
7.9% Ag, 18.6% Cd, and 0.4% K by weight. Powder X-ray diffraction study Tevealed stTong lines due to CdO, and weak lines due to Ag.
About 2.5 grams of this ~aterial were charged to a 0.55 cm i.d. by 28 cm reactor tube. Under 197 psig hydrogen flowing at 750 SCCM
the ten,perature was raised from 24C to 125C o~er the course of l.l hours, at which time 1 part acrolein in 40 parts hydrogen replaced the pure hydrogen~ Table IV lists the reaCtOT conditions and the analysis o~ the liquid products collected in a trap held at -78C under reactor pressure. ;
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X-ray diffraction analysis of the used catalyst indicated the presence of ~-phase AgCd, y-phase alnd fiome ~-~hase AgCd alloys.
~No discrete metallic cadmium or silver was observed. Lines were observed ~t 2.41, 2.36, 2.08, A, and a sharp line characteristic of y at 1.67. The back reflection was weak. ~ulk chemical analysis indicated that these alloys had an average composition of 29.8% Ag and 70.2~ Cd.
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I i ~37S9~7 EXAMPLB V
A solution of 34~l grams AgN03 ~0~20 mole) and 60.2 grams Cdo~03~2~2H20 (0.195 mole) in 20Q millilitess of water was added simultan~
eously with a solution of 34.95 grams of 87 4% analy1;ical reagent grade K0~ co-s~l molel in 200 milliliters o water to 400 milliliters of rapidly stirred distilled water The pH of the supernatant phase after addition was 6 0, The volume of the suspension was increased to 1500 milliliters, and lnoo milliliters of Cab-0-Sil* M-5 (a fumed silica) were added with vigorous stirring. The total volume was adjusted to 200n milliliteTs and the slurry was filtered~ The filter cake was washed with 3000 milli~
liters o distilled ~ater, calcined in air at 250C for 21 5 hours> and the ~esulting catalyst precursor was crushed ~nd screened to yield a `~
sn sa mesh ~ractlon. Chemical analysis indicated that the compOSitiQn cont~lned 49~6% SiO2, 2$~9~ Ag, 18,6~ Cd, and 0.4~ K. Powder X-ray diPPraction indicated that motallic silvel and cadmium oxid0, CdO, b~th o~ medium order were present at this stage, besides the amorphouc SiO2 which did not contribute detectable X-ray diffraction lines.
A 7,35 grams quantity of this catalyst precursor were placed `~
in a 0.~25 cm i.d. by 28 cm reactor tube~ Under 499 psig hydrogen flowing at 1500 SCCM, the reactor was heated ~o 200C from 18OCJ maintained at 200C for 15 minutes, and cooled to 125C over a total period of one hour.
The hydrogen was then replaced by 1 part acrolein in 111 parts hydrogen.
Ta~le V summarizes the results based on the analysis o liquid products collected at -78C undex reactor pressure.
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,l A 2.71 gram quantity of the catalyst precursor was placed in a 0.55 cm i.d. by 28 cm reactor tube, and u~der 620 psig jhydrogen flowing at lS00 SCCM the material was heated from 10C
; to 200C over a period of one hour. The catalyst was maintained ~ `~
~i at 200C for 15 minutes and then cooled rapidly to 1~5C, at which time an acrolein/hydrogen stream replaced the pure hydrogen.
Table V summarizes various reactor conditions and th~e composition of the liquid products collected in a trap held at ;~ -78C and reactor pressure. ;
~, X-ray diffraction analysis of the used catalyst indicated that the principal AgCd alloy was the a-phase. Bulk chemical ana~ysis indicated that the average composition o~ khe silver-cadmlum alloy on sil1ca wa~ 58.2~ ~g and ~l.8~ Cd.
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A 28~77 gram quantity of analytical reagent grade KOH t0~446 ~-molel was added to 20Q milliliters of distilled wa~er~ and the resultant solution ~as warmed to 100C. With rapid s~irring a solution of 25.26 grams AgN03 ~0~149 mole) and 45.85 grams CdoN03)2.4H20 (0.149 mole) in lQ0 milliliters o~ distilled water was added. The suspension was cooled and diluted by the addition of 1000 milliliters of 2C distilled water ~`
followed by 100 milliliteTs of Cab~O-Sil* M-5 (a fum~d silica). Additional distilled water was added to adjust the total volume to 1800 milliliters.
The pH o the supernatant phase ~as 6.5, ~;;
The suspension was vacuum filtered, and the filter cake was ~ashed wlth 2000 milli~t~rs of distilled water and calcined ln alr at 250C ~or 20 hours. The catalyst precursor was thon crushed ancl screencd to provide a 50-80 mesh fraction. X-ray dif~raction examinntion revealed principally CdO of medium orderS and no detestable silver lines.
A 4.04 gram quantity of this material was placed in a 0.55 cm i.d. by 28 cm reactor tube. The reactor under 490 psig hydrogen flow-ing at 1500 SCCM was heated f~om :70C to 200C, held at 200C for lS ~ ;
minutes and cooled to 125 C over the course of 1.6 hours~ At this time, 2Q the h~drogen was replaced by 1 part acrolein in 109 parts hydrogen. Table YI sum~arizes various reactor condition~, and the resultant composition of liquid products collected in a trap held at -78C and reactor pressure.
The used catalyst, 5~7% silica with 65.7% alloys, consisted of well ordered a,y and some ~-phase AgCd alloy on SiO2~ The aYerage alloy composition was 52.4% Ag and 46.6% Cd.
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To a solution of silver and cadmium nitrates containing 102 grams AgN03 C0.600 mole) and 138.9 Cd(N03)2.2~120 (0.450 mole) in 150 milliliteIs of distillcd water, a solution of 60.9 grams of 98.6~
analytical reagent grade NaOH in 150 milliliters of clistilled water was added with rapid stirring. The resultant black gel turned light brown on -suspending in an additional 1500 milliliters of doubly distilled water.
The precipitate was separated from the solution by vacuum filtration, washed with 2000 milliliters of doubly distilled water, and then ground in a mortar and pestle with 150 milliliters of DuPont Ludox AS~ Colloidal Silica. The mixture was dried for 20 hours at 95C, and calcined in air at 200C for 60 hours. The mixture was then crushed and screened to yleld ~ 5~-80 mesh raction. The composition contained 18.8% SiO2, 27.2~ Ag and 30.6% Cd.
A 13,10 gram quantity of this material was placed in a 0.925 cm i.d. by 28 cm reactor tube. ~lder 100 psig gas (9~% He, 1% H2) flowing at 200 SCCM, the temperature was raised in 12 minutes to 75C, then at 25C per hour to 25QC and maintained at the final temperature for 65 hours The catalyst was cooled to 125C, and the gas stream was changed to 510 psig hydrogen flowing at 1500 SCCM After 24 minutes, the gas was changed to 1 part acrolein in 113 parts hydrogen. Iable VII
summarizes various reactor conditions and the resultant composition of the liquid products collected in a trap held at -78C and reactor pressure.
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The used catalyst had a nitrogen BET surface area of 9.6 m2/grams, and contained primarily yAgCd, with ~ and some E AgCd alloy, all on silica. The average composition of the AgCd alloys was 54.9% Ag and 45.1% Cd.
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EXAMPLE VIII - -One hundred milliliters of 30 mesh Girdler* Silica T-1571, (a ;~ ;
3~16 inch spherical) silica ca1Tier was cautiously aclded to one liteT of -~ parts concentrated nitric acid and 1 part concentrated pe~chloric acid.
The mixture was heated and maintained at reflux temperature for 6 hours.
After cooling to room temperature, the silica was washed with distilled water se~eral times and then placed in a Soxhlet* ~x~ractor with distilled ~-water and calcium oxide in the water-boiling flask. The silica was then extracted ~OT 24 hours, after which time the extraction liquid was neutral.
The silica was dried by flowing oxygen gas at one atmosphere o~er the material at 525-535C for six hours. The dried material was transferred to a flask) and admixed with a solution contalning 0.72 mole AgN03 and 0~35 mole of Cd(N03)2 in 200 millillteTs of wat0r. ~ ;
The nlaterlal was r0cover0d and plac0d in a glass tub0 on a yacuum system, and initial drying was accomplished at 100 Torr by conn~ctlng the tube to a liquid nitrogen cooled trap. The tube was heated to 300C
and the pressure was reduced to 10-4 Torr fo~ 30 minutes, t.hen S psig hydrogen gas was introduced, Brown nitrogen oxide fumes resulted ~ld the pressure was again reduced to 10-4 Torr for 15 minutas. This cycle was repeated until no brown fumes were noticeable. The pressure was reduced to 10 4 Torr for 15 minutes and then 1 atm hydrogen was introduced. The catalyst was allowed to cool under hydrogen to room temperature, at whicll t~me the hydrogen was replaced with nitrogen and the catalyst was re ved.
Powder X~ray diffraction analysis indicated that a-phase AgCd alloy was p~esent on the silica.
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, ' ., ~, A 7.85 gram quantity of the catalyst was placed in a 0.925 cm i.d. by 28 cm reactor tube. The catalys~, under 509 psig hydrogen flowing at 200 SCCM, was rapidly heated to 25~C and maintained under those conditions for 2:l.4 hours. The temperature :iwas graudally reduced to 125C, and then lthe hydrogen was replaced :by l part acrolein in lO0 parts of hydrogen.
Table VIII summarizes various reactor conditions an~ the resultant composition of the liquid products collected by a trap held at -78C at reactor pressure.
The used catalyst wa~ analyzed as containing 69.7~ SiO2, 3.7% Cd and 7.2~ Ag, and had a nitrogen BET surface area of 53.6 m2/g. The 66.1~ silver, 33.9~ cadmlum ~-phase alloy on the silica exhibited a X-ray diffraction pattern o~ moderate order.
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This Example illustrates the low conversions and low yields; `~
obtained when a silver~cadmium catalyst not in accordance with the ~- present ~nvention contains unalloyed silver crystalllites.
A solution of 34 grams AgN03 (0.200 mole) and 30 grsms ;~
Cd~NO3)2.4H2O ~0.097 mole) in 100 milliliters of clistilled water was added with rapid stirring to 15.6 grams NH4HC03 ~0.1g7 mole) in 150 milli- -liters of distilled water, Carbon dioxide evolved and a yellow precipitate formed. With vigorous stirring to keep the precipitate in suspension,`- ;~
~ 10 200 milliliters of Cab-O-Sil* M 5 (a fumed silica) was added and 1:he;~ resultant suspension stirred gently for 2 hours and allowed to settle~;~
ove~night~ The solids were filtered and washed with 500 milliliters o~
4C distilled water. The ~ilter cake was dried and crushed and screened to yield a 50-80 mesh ~ractlon~ Bulk chemical analysis and powder X-ray difraction analysis indicated that the catalyst precursor consisted of 48~% Ag as Ag crystallites, 28.0% Cd as CdO, and 20 4% SiO2 by weight.
A 2.97 gram quantit~y of the 50-80 mesh ~raction was placed in ``
a 0~25 cm i.d. by 28 cm reactor tube, and 203 psig hydrogen flowing at ;~ 75Q SCCM was passed over the catalyst as the temperature was increased 2Q ~rcm 24C to 125C over a period of 24 minutes. One part acrolein in 40 pa~ts hydrogen was then substituted for the pure hydrogen gas. Table IX ~;
summarizes the results obtained by gas chromatographic analysis of the reactor effluent stream~
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; The used catalyst, which analyzed as 30.9 Ag, 17.4% Cd and 29.7~ Si~2 (64% Ag and 36% Cd on a metal basis), was found ~ : by X-ray diffraction studies to have an AgCd phase containing ! ' -AgCd and y-AgCd, and large pure Ag crystallites which indicated 3 I that a significant portion of the silver was ~ot alloyed. The X-ray diffraction lines were at 2.40, 2.36, 2.04, 1.46-7~ 1.44, 1.25, and 1.23. The ~g lines and back reflection indicated the presence of laxge Ag crystals. The AgCd associated lines and back reflection were sharp.
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EXAMPLe X ;~ ;
This Example illustrates the low conversions and low yields !`
obtained when a silver-cadmium catalyst not in accordance with the present i; invention contains a manor quantity of silver metal and consists sub- stantially of cadmium metal on a carrier substrate.
Two solutions were prepared by dissolving 1.01 grams AgN03 C0.006 molel and 89~91 grams Cd(N03)2,4H20 ~0.291 mole) in 100 distilled ~ater, and dissolving 37 81 grams 87.4% reagent grade KOH ~0.589 mDle) "
, in 100 milliliters of distilled water. Both solutions were added rapidly and simultaneously to 200 millilite~s of vigorously stirred distilled water, The pH of the liquid medium was about 6.5, About 500 milllliters ~ o Cab-O~Sil~ M-S ~a fumad silica~ were added along with suficient wator $ t~ keep tho nledium fluid, The volume was ad~usted to }800 milliliters ~; with additional distilled water. ;~
A filter cake was recovered by vacuum filtration, washed with 2000 milliliters of distilled water, and then calcined in air at 250C
~or 17.5 hours. The reddish tan catalyst precursor was cooled to Toom temperature in a vacuum desiccatox prior to being crushed and screened to provide a 50 80 mesh fraction. Chemical analysis indicated that the con~osition contained 32~ SiO2, 51~ Cd, and 1% Ag. CdO of medlum order was the Cd species found by X-ray diffraction.
A 8.15 gram quantity of this material were placed in a 0.925 cm i.d. by 28 cm reactor tube. The material was heated under 499 psig hydrogen flowing at 1400 SCCM from 18C to 200C, maintained at 200C
for 15 minutes, and cooled to 125 C over a ," ~
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total period of 1.6 hours. 1 par~ acrolein in 40 parts hydrogen was intorduced 12 minutes later.
Table X ~ummarize~ various reactor conditions and the resultant composition of the liquid products collected in a trap at -78C and reactor pressure.
The used catalyst, by ~-ray diffraction, appeared to have well ordered cadmium rich ~-phase AgCd with a structure not differing significantly from metallic Cd. The average composition of this alloy was 2% silver and 98% cadmium by chemical analysis.
The used catalyst had a nitrogen B~T surface area of 71.4 m2/gram.
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This Example illustrates the low yields obtained when a silveT-cadmium catalyst not in accordance with the present inYentiOn contains a minor quanti~y of cadmium metal and consists substantially of silver metal on a carrier substrate, To a solution o~ silver and cadmium nitraLtes prepared by adding 102 grams AgN03 C0.600 mole~ and 90 grams Cd(NO3)2.4H20 ~0.292 mole) to 120 milliliters of distilled water, 120 milliliters of 1 normal sodium hydxoxide solution was added with rapid stirring. The resultant pre-cipitate was separated from the solution by vacuum filtration, washed with 600 milliliters oE distilled water> and resuspended in 90 milliliters ~ ~:
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of DuPont Ludox AS* Colloidal Silica with rapid stirring. The suspensian t was air dricd at 100C for 17 hours, and calcined at 250C for 20 hours i in air, The catalyst precursor was cooled in a vacuum desiccator, and f then crushed and screened to yield a 50-80 mesh fraction. By chemical ~, analysis it was determined that the composition contained 45.4% silica, 27.~% silYer, 1% cadmium and 2.8% sodium. Well ordered crystals of CdO, `
Cd(0H~2 and Ag were present.
A 3 96 gram quantity of this material was placed in a 0.55 cm i.d. by 28 cm reactor tube. Under 494 psig hydrogen flowing at 1300 SCCM the reactor was ~apidly heated from 18C to 250C, held at 250C
or 30 Dlinutes, and then cooled to 125C. A~ter an additional six r~nutes, 1 part acrolein in 110 parts hydrogen was introduced. Table XI
- summarizes reactor conditions and tha resultant composition of the ~i pxoducts collected in a trap held : ,.
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5~7 - ,at -78C and reactor pressure. The used cataly5t had o nitrogen surface area of 81.5 m2jgram, and powder X-ray diffraction examination identi~ied well ordered silver crystals on silica.
The used catalyst had a 96.5% silver and 3.5% cadmium metal alloy ~¦
. content.
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EXA~IPLE III
For the preparation of a silver-cadmium solution, 34~7 gTams AgNO3 ~0 204 mole~ and 80.0 grams CdCNO3)2~4H2O (0 259 mole) were dissolved in 100 milliliters of distilled water. To this solution was added 17.0 grams of 86~7% KOH (0~263 ~ole) dissolved in 50 milliiliters of distilled water, followed by addition of 400 milliliters of distilled wa~er. l~e ~lurry mixture which formed was added to 400 milliliters of Cab-O-Sil*
M~5 (a fumed silica~ suspended in one liter of distilled water with rapid stirring. The resultant solids were filtered off, partially air dried overnight, and calcined in air at 250C for 16 hours. ~fter cooling in a vacuum desiccator, the material was partially crushed and extracted with distilled water for about 24 hours, then recalcined a~ 250C to 300C
Por 21 hours in air~ The resultant material contained 34~ by w~lght silver, present as metallic crystallites, 17.9% by weight cadmi~m- as cadmiw~
hydxoxide crystallites of two types, and 33% by weight of silica, with less than 0.05% K or Cl.
This material was crushed and screened to yield a 50-80 mesh fraction, 3,16 grams of which were loaded into 0.925 cm i.d, by 28 cm reactor tu~e~ Hydrogen gas at 200 psig was passed over the catalyst at 2Q 750 SCCM and the temperature brought rapidly rom 22C to 127 C; then the gas was chang0d to l part ucrolein in approximately 40 parts hydTogen.
Table III summaTizes the results obtained under various conditions employing this catalyst. The reactoT effluent stream was analyzed by gas chromatographic techniques. Table III summarizes ',''; .":
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the reactor conditions, and the analysis of liquid products trapped at -78~ in a collection vessel down stream rom the reactor. Bulk chemical analysis of ths used cataly~t in coniunction with X-ray diffraction scanning indicated that an tl ~-phase alloy with an average bulk composition of 62.9% silve~
and 37.1% cadmi~m was present. Broad X-ray diffraction lines at 2.36, 2.05, 1.45, and 1.23 A along with broad back reflection lines were observed, which indicated the presence of ~-phase silver-cadmium. No discrete silver or cadmium metallic crystal- !
lites were detected.
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EXAMPLE IV
A solution was prepared by dis~olving 13.07 grams AgN03 (0.077 molel and 37~97 grams Cd~N03)2~4H20 ~0,123 mole) in l00 milliliters o `
distilled water. A second solution was pTepared by d ssol~ing 20.75 grams of 87.4% analytical reagent grade KOH in (0.32 mole) 100 milliliters of distilled water. Both solutions were then rapidly and simultaneously added to a vigorously stirred 100 mîlliliters of distilled water, and ~ ;~
the resulting precipitate was further suspended by the addition of 500 milliliters of distilled WateT After 1 hour of stirring, 1000milliliters of Cab-O.Sil* M-5 (a fumed silica) were added, in addition to sufficient water at intervals to maintain mixture fluidity. The final volum~ was increased to 1800 nilliliters. The p~l of the superna~ant phas~ was 6.5.
V~cuum ~iltration was omployed to produce a iltor ca~o, which was washed with 2000 milliliters of distilled w~ter. The filter cukc was calclned in air at 250 for 25 hours. After cooling in a vacu~m desiccator, the catalyst pTeCurSOr was crushed and screened to yield a 5d-80 mesh ~raction.
Bulk chemical analysis indicated that the catalyst contained 63.7% SiO2~
7.9% Ag, 18.6% Cd, and 0.4% K by weight. Powder X-ray diffraction study Tevealed stTong lines due to CdO, and weak lines due to Ag.
About 2.5 grams of this ~aterial were charged to a 0.55 cm i.d. by 28 cm reactor tube. Under 197 psig hydrogen flowing at 750 SCCM
the ten,perature was raised from 24C to 125C o~er the course of l.l hours, at which time 1 part acrolein in 40 parts hydrogen replaced the pure hydrogen~ Table IV lists the reaCtOT conditions and the analysis o~ the liquid products collected in a trap held at -78C under reactor pressure. ;
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X-ray diffraction analysis of the used catalyst indicated the presence of ~-phase AgCd, y-phase alnd fiome ~-~hase AgCd alloys.
~No discrete metallic cadmium or silver was observed. Lines were observed ~t 2.41, 2.36, 2.08, A, and a sharp line characteristic of y at 1.67. The back reflection was weak. ~ulk chemical analysis indicated that these alloys had an average composition of 29.8% Ag and 70.2~ Cd.
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A solution of 34~l grams AgN03 ~0~20 mole) and 60.2 grams Cdo~03~2~2H20 (0.195 mole) in 20Q millilitess of water was added simultan~
eously with a solution of 34.95 grams of 87 4% analy1;ical reagent grade K0~ co-s~l molel in 200 milliliters o water to 400 milliliters of rapidly stirred distilled water The pH of the supernatant phase after addition was 6 0, The volume of the suspension was increased to 1500 milliliters, and lnoo milliliters of Cab-0-Sil* M-5 (a fumed silica) were added with vigorous stirring. The total volume was adjusted to 200n milliliteTs and the slurry was filtered~ The filter cake was washed with 3000 milli~
liters o distilled ~ater, calcined in air at 250C for 21 5 hours> and the ~esulting catalyst precursor was crushed ~nd screened to yield a `~
sn sa mesh ~ractlon. Chemical analysis indicated that the compOSitiQn cont~lned 49~6% SiO2, 2$~9~ Ag, 18,6~ Cd, and 0.4~ K. Powder X-ray diPPraction indicated that motallic silvel and cadmium oxid0, CdO, b~th o~ medium order were present at this stage, besides the amorphouc SiO2 which did not contribute detectable X-ray diffraction lines.
A 7,35 grams quantity of this catalyst precursor were placed `~
in a 0.~25 cm i.d. by 28 cm reactor tube~ Under 499 psig hydrogen flowing at 1500 SCCM, the reactor was heated ~o 200C from 18OCJ maintained at 200C for 15 minutes, and cooled to 125C over a total period of one hour.
The hydrogen was then replaced by 1 part acrolein in 111 parts hydrogen.
Ta~le V summarizes the results based on the analysis o liquid products collected at -78C undex reactor pressure.
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,l A 2.71 gram quantity of the catalyst precursor was placed in a 0.55 cm i.d. by 28 cm reactor tube, and u~der 620 psig jhydrogen flowing at lS00 SCCM the material was heated from 10C
; to 200C over a period of one hour. The catalyst was maintained ~ `~
~i at 200C for 15 minutes and then cooled rapidly to 1~5C, at which time an acrolein/hydrogen stream replaced the pure hydrogen.
Table V summarizes various reactor conditions and th~e composition of the liquid products collected in a trap held at ;~ -78C and reactor pressure. ;
~, X-ray diffraction analysis of the used catalyst indicated that the principal AgCd alloy was the a-phase. Bulk chemical ana~ysis indicated that the average composition o~ khe silver-cadmlum alloy on sil1ca wa~ 58.2~ ~g and ~l.8~ Cd.
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A 28~77 gram quantity of analytical reagent grade KOH t0~446 ~-molel was added to 20Q milliliters of distilled wa~er~ and the resultant solution ~as warmed to 100C. With rapid s~irring a solution of 25.26 grams AgN03 ~0~149 mole) and 45.85 grams CdoN03)2.4H20 (0.149 mole) in lQ0 milliliters o~ distilled water was added. The suspension was cooled and diluted by the addition of 1000 milliliters of 2C distilled water ~`
followed by 100 milliliteTs of Cab~O-Sil* M-5 (a fum~d silica). Additional distilled water was added to adjust the total volume to 1800 milliliters.
The pH o the supernatant phase ~as 6.5, ~;;
The suspension was vacuum filtered, and the filter cake was ~ashed wlth 2000 milli~t~rs of distilled water and calcined ln alr at 250C ~or 20 hours. The catalyst precursor was thon crushed ancl screencd to provide a 50-80 mesh fraction. X-ray dif~raction examinntion revealed principally CdO of medium orderS and no detestable silver lines.
A 4.04 gram quantity of this material was placed in a 0.55 cm i.d. by 28 cm reactor tube. The reactor under 490 psig hydrogen flow-ing at 1500 SCCM was heated f~om :70C to 200C, held at 200C for lS ~ ;
minutes and cooled to 125 C over the course of 1.6 hours~ At this time, 2Q the h~drogen was replaced by 1 part acrolein in 109 parts hydrogen. Table YI sum~arizes various reactor condition~, and the resultant composition of liquid products collected in a trap held at -78C and reactor pressure.
The used catalyst, 5~7% silica with 65.7% alloys, consisted of well ordered a,y and some ~-phase AgCd alloy on SiO2~ The aYerage alloy composition was 52.4% Ag and 46.6% Cd.
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To a solution of silver and cadmium nitrates containing 102 grams AgN03 C0.600 mole) and 138.9 Cd(N03)2.2~120 (0.450 mole) in 150 milliliteIs of distillcd water, a solution of 60.9 grams of 98.6~
analytical reagent grade NaOH in 150 milliliters of clistilled water was added with rapid stirring. The resultant black gel turned light brown on -suspending in an additional 1500 milliliters of doubly distilled water.
The precipitate was separated from the solution by vacuum filtration, washed with 2000 milliliters of doubly distilled water, and then ground in a mortar and pestle with 150 milliliters of DuPont Ludox AS~ Colloidal Silica. The mixture was dried for 20 hours at 95C, and calcined in air at 200C for 60 hours. The mixture was then crushed and screened to yleld ~ 5~-80 mesh raction. The composition contained 18.8% SiO2, 27.2~ Ag and 30.6% Cd.
A 13,10 gram quantity of this material was placed in a 0.925 cm i.d. by 28 cm reactor tube. ~lder 100 psig gas (9~% He, 1% H2) flowing at 200 SCCM, the temperature was raised in 12 minutes to 75C, then at 25C per hour to 25QC and maintained at the final temperature for 65 hours The catalyst was cooled to 125C, and the gas stream was changed to 510 psig hydrogen flowing at 1500 SCCM After 24 minutes, the gas was changed to 1 part acrolein in 113 parts hydrogen. Iable VII
summarizes various reactor conditions and the resultant composition of the liquid products collected in a trap held at -78C and reactor pressure.
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The used catalyst had a nitrogen BET surface area of 9.6 m2/grams, and contained primarily yAgCd, with ~ and some E AgCd alloy, all on silica. The average composition of the AgCd alloys was 54.9% Ag and 45.1% Cd.
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EXAMPLE VIII - -One hundred milliliters of 30 mesh Girdler* Silica T-1571, (a ;~ ;
3~16 inch spherical) silica ca1Tier was cautiously aclded to one liteT of -~ parts concentrated nitric acid and 1 part concentrated pe~chloric acid.
The mixture was heated and maintained at reflux temperature for 6 hours.
After cooling to room temperature, the silica was washed with distilled water se~eral times and then placed in a Soxhlet* ~x~ractor with distilled ~-water and calcium oxide in the water-boiling flask. The silica was then extracted ~OT 24 hours, after which time the extraction liquid was neutral.
The silica was dried by flowing oxygen gas at one atmosphere o~er the material at 525-535C for six hours. The dried material was transferred to a flask) and admixed with a solution contalning 0.72 mole AgN03 and 0~35 mole of Cd(N03)2 in 200 millillteTs of wat0r. ~ ;
The nlaterlal was r0cover0d and plac0d in a glass tub0 on a yacuum system, and initial drying was accomplished at 100 Torr by conn~ctlng the tube to a liquid nitrogen cooled trap. The tube was heated to 300C
and the pressure was reduced to 10-4 Torr fo~ 30 minutes, t.hen S psig hydrogen gas was introduced, Brown nitrogen oxide fumes resulted ~ld the pressure was again reduced to 10-4 Torr for 15 minutas. This cycle was repeated until no brown fumes were noticeable. The pressure was reduced to 10 4 Torr for 15 minutes and then 1 atm hydrogen was introduced. The catalyst was allowed to cool under hydrogen to room temperature, at whicll t~me the hydrogen was replaced with nitrogen and the catalyst was re ved.
Powder X~ray diffraction analysis indicated that a-phase AgCd alloy was p~esent on the silica.
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Table VIII summarizes various reactor conditions an~ the resultant composition of the liquid products collected by a trap held at -78C at reactor pressure.
The used catalyst wa~ analyzed as containing 69.7~ SiO2, 3.7% Cd and 7.2~ Ag, and had a nitrogen BET surface area of 53.6 m2/g. The 66.1~ silver, 33.9~ cadmlum ~-phase alloy on the silica exhibited a X-ray diffraction pattern o~ moderate order.
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This Example illustrates the low conversions and low yields; `~
obtained when a silver~cadmium catalyst not in accordance with the ~- present ~nvention contains unalloyed silver crystalllites.
A solution of 34 grams AgN03 (0.200 mole) and 30 grsms ;~
Cd~NO3)2.4H2O ~0.097 mole) in 100 milliliters of clistilled water was added with rapid stirring to 15.6 grams NH4HC03 ~0.1g7 mole) in 150 milli- -liters of distilled water, Carbon dioxide evolved and a yellow precipitate formed. With vigorous stirring to keep the precipitate in suspension,`- ;~
~ 10 200 milliliters of Cab-O-Sil* M 5 (a fumed silica) was added and 1:he;~ resultant suspension stirred gently for 2 hours and allowed to settle~;~
ove~night~ The solids were filtered and washed with 500 milliliters o~
4C distilled water. The ~ilter cake was dried and crushed and screened to yield a 50-80 mesh ~ractlon~ Bulk chemical analysis and powder X-ray difraction analysis indicated that the catalyst precursor consisted of 48~% Ag as Ag crystallites, 28.0% Cd as CdO, and 20 4% SiO2 by weight.
A 2.97 gram quantit~y of the 50-80 mesh ~raction was placed in ``
a 0~25 cm i.d. by 28 cm reactor tube, and 203 psig hydrogen flowing at ;~ 75Q SCCM was passed over the catalyst as the temperature was increased 2Q ~rcm 24C to 125C over a period of 24 minutes. One part acrolein in 40 pa~ts hydrogen was then substituted for the pure hydrogen gas. Table IX ~;
summarizes the results obtained by gas chromatographic analysis of the reactor effluent stream~
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; The used catalyst, which analyzed as 30.9 Ag, 17.4% Cd and 29.7~ Si~2 (64% Ag and 36% Cd on a metal basis), was found ~ : by X-ray diffraction studies to have an AgCd phase containing ! ' -AgCd and y-AgCd, and large pure Ag crystallites which indicated 3 I that a significant portion of the silver was ~ot alloyed. The X-ray diffraction lines were at 2.40, 2.36, 2.04, 1.46-7~ 1.44, 1.25, and 1.23. The ~g lines and back reflection indicated the presence of laxge Ag crystals. The AgCd associated lines and back reflection were sharp.
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This Example illustrates the low conversions and low yields !`
obtained when a silver-cadmium catalyst not in accordance with the present i; invention contains a manor quantity of silver metal and consists sub- stantially of cadmium metal on a carrier substrate.
Two solutions were prepared by dissolving 1.01 grams AgN03 C0.006 molel and 89~91 grams Cd(N03)2,4H20 ~0.291 mole) in 100 distilled ~ater, and dissolving 37 81 grams 87.4% reagent grade KOH ~0.589 mDle) "
, in 100 milliliters of distilled water. Both solutions were added rapidly and simultaneously to 200 millilite~s of vigorously stirred distilled water, The pH of the liquid medium was about 6.5, About 500 milllliters ~ o Cab-O~Sil~ M-S ~a fumad silica~ were added along with suficient wator $ t~ keep tho nledium fluid, The volume was ad~usted to }800 milliliters ~; with additional distilled water. ;~
A filter cake was recovered by vacuum filtration, washed with 2000 milliliters of distilled water, and then calcined in air at 250C
~or 17.5 hours. The reddish tan catalyst precursor was cooled to Toom temperature in a vacuum desiccatox prior to being crushed and screened to provide a 50 80 mesh fraction. Chemical analysis indicated that the con~osition contained 32~ SiO2, 51~ Cd, and 1% Ag. CdO of medlum order was the Cd species found by X-ray diffraction.
A 8.15 gram quantity of this material were placed in a 0.925 cm i.d. by 28 cm reactor tube. The material was heated under 499 psig hydrogen flowing at 1400 SCCM from 18C to 200C, maintained at 200C
for 15 minutes, and cooled to 125 C over a ," ~
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total period of 1.6 hours. 1 par~ acrolein in 40 parts hydrogen was intorduced 12 minutes later.
Table X ~ummarize~ various reactor conditions and the resultant composition of the liquid products collected in a trap at -78C and reactor pressure.
The used catalyst, by ~-ray diffraction, appeared to have well ordered cadmium rich ~-phase AgCd with a structure not differing significantly from metallic Cd. The average composition of this alloy was 2% silver and 98% cadmium by chemical analysis.
The used catalyst had a nitrogen B~T surface area of 71.4 m2/gram.
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This Example illustrates the low yields obtained when a silveT-cadmium catalyst not in accordance with the present inYentiOn contains a minor quanti~y of cadmium metal and consists substantially of silver metal on a carrier substrate, To a solution o~ silver and cadmium nitraLtes prepared by adding 102 grams AgN03 C0.600 mole~ and 90 grams Cd(NO3)2.4H20 ~0.292 mole) to 120 milliliters of distilled water, 120 milliliters of 1 normal sodium hydxoxide solution was added with rapid stirring. The resultant pre-cipitate was separated from the solution by vacuum filtration, washed with 600 milliliters oE distilled water> and resuspended in 90 milliliters ~ ~:
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of DuPont Ludox AS* Colloidal Silica with rapid stirring. The suspensian t was air dricd at 100C for 17 hours, and calcined at 250C for 20 hours i in air, The catalyst precursor was cooled in a vacuum desiccator, and f then crushed and screened to yield a 50-80 mesh fraction. By chemical ~, analysis it was determined that the composition contained 45.4% silica, 27.~% silYer, 1% cadmium and 2.8% sodium. Well ordered crystals of CdO, `
Cd(0H~2 and Ag were present.
A 3 96 gram quantity of this material was placed in a 0.55 cm i.d. by 28 cm reactor tube. Under 494 psig hydrogen flowing at 1300 SCCM the reactor was ~apidly heated from 18C to 250C, held at 250C
or 30 Dlinutes, and then cooled to 125C. A~ter an additional six r~nutes, 1 part acrolein in 110 parts hydrogen was introduced. Table XI
- summarizes reactor conditions and tha resultant composition of the ~i pxoducts collected in a trap held : ,.
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5~7 - ,at -78C and reactor pressure. The used cataly5t had o nitrogen surface area of 81.5 m2jgram, and powder X-ray diffraction examination identi~ied well ordered silver crystals on silica.
The used catalyst had a 96.5% silver and 3.5% cadmium metal alloy ~¦
. content.
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EXAMPLE XII ! ;! -: This Example illustrates thc l~wer conversions obtained when a silver-cadmium catalyst not in accordance with the present invention contains coprecipitated silver-cadmium alloy without a carrier substrate.
Two solutions were prepared by dissolving 34.0 grams AgNO3 (0.200 mole~ and 41.2 grams Cd(NO3)2 4H2O ~0.134 mole) in ; 100 milliliters of distilled water, and 30.12 grams of 97.0%
i analytical reagent grade KOH (0.537 mole) in 100 milliliters of I distilled ~ater. Both solu~ions were added simultaneously and in a rapid dropwise fashion to 400 milliliters of vigorously stirred distilled water. ~he pH was adjusted to 7.0 with ~OH or Xl~03 I as needed, and the volume was increased with distilled water to , 2000 milliliters. The suspension was allowed to settle at 4C, j' protected from light. The clear supernatant liquid was~drawn off and fresh distilled water was added to adjust~the volume to~
2000 milliliters. Il The solids were recovered from the solution by vacuum filtration, washed with 2000 milliliters of distilled water, and calcined in air at 200C for 20 hours. After cooling in a vacuum , desiccator, the material was crushed and sieved to~yield a -I 50-80 mesh fraction. Chemical analysis indicated that the bulk `I material was 55.6% Ag and 43.4~ Cd.
, A 6.83 yram quantity of thio material was~placedjin a ; 0.55 cm i.d. by 28 cm reactor tube. sOver a period o~ twc hours.
, the catalyst was treated with 501 psig hydrogen }lowing at }500 ¦
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SCCM heated from 24 to 250C, held at 2S0C for 15 minutes, and : cooled to 125C. At this time, 1 part acrolein in 111 parts . hydrogen replaced the pure hydrogen f:low stream.
Table XII summarizes various reactor conditions and the i, resultant composition of the liquid products collected in a trap ; held at -78C and reactor pressure. The used catalyst had a nitrogen BET surface area of 0.15 m2/gram, and was a mixture , of ~,y with some E-phase silver-cadmium alloys. I
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EXAMPLE XIII -This Example illustrates the conversions and yields obtained t~ :
when a silver-cadmium alloy catalyst contains copper metal, ~ ~
Two solutions were prepared by dissolving 34.00 grams AgN03 ~ ~ ;
CO,20015 mole~, 30,00 grams Cd(N03)2.4H20 (0.09725 mole), and 0.60 gram Cu(N03)2.3H20 ~0~00248 mole) in 100 milliliters of distilled water, and 25.70 grams of 87.4% analytical reagent grade KO~I ~0.4003 mole) in 100 milliliters of distilled water. Both solutions were added rapidly and simultaneously to 100 milliliters of vigorously stirred distilled water. ;~
After the formation of the blackish gelatinous precipitate, the volume of the system was adjusted to lOOO milliliters with aclditional distilled water. The pH of the supernatant was 6~5, lOOO milliliters of Cab-O-Sil*
M-S (a umed silica) and sufficient water to adjust the total volume to 18QQ milliliters were added~ The precipitate was removed rom the super-na~ant solution by vacuum filtration and washed with 2Q~O milllliters of distilled water. The solid was then calclned in air at 250C ~or 20 hours. The material was crushed and sieved to yield a 50-80 mesh fruction.
..
The composition analyzed as containing 53.7% SiO2, 26.9% Ag, 16.9% Cd, 0.5% K, and 0,8% Cu. Powder X-ray diffraction examination identified ~; 2Q only lines indicating CdO.
A 7,72 grams quantity of this material was placed in a 0.925 cm i.d. by 29 cm reactor tube. With 500 psig hydrogen flowing over the ;~
catalyst precusor at 1500 SCCM, the temperature of the reactor was increased from 19C to 200C, held at 200C for 15 minutes, and cooled to 125C. The hydrogen stream was replaced ~T~adem~k ::
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' with 1 part acrolein in 110 parts hydrogen.
~able XIIIsummarizes various reactor conditions and the resultant composition of liquid products collected in a trap held at -78C and reactor pressure. q~he used catalyst had a ,! surface area of 47.8 m2/gm~ and exhibited a silver rich ~-phase I AgCd(Cu) alloy on silica with an averaye composition of 60.31%~
Ag, 37.89~ Cd and 1.79% Cu. ~; ' In the same manner, a second catalyst was prepared with a Jl s i , ~
. bulk content of 54.4~ SiO2, 31.6% Ag, 14.1~ Cd, and about 660 ppm !
. , cu.
Table XIII-A gu~rizes various reactor conditions and the resultant composition of the liquid products collected in a trap ;held at 78~C and reactor pressure employing the second catalyst.
; The used catalyst, on powder X-ray diffraction examination, o ~ ~
~ exhibited sharp lines at 2.36, 2.04, 1.44, 1.23 A, with a-strong ~ ~ ~
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sharp back re~lection pattern eviden~. Chemical analysis ~ indicated a silver rich ~i-phase AgCd(Cu) alloy of 69.0~ Ag, ,, . ~.
30.8% Cd, and 0.14~ Cu average composition on the silica. ~
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EXAMPLE XIV
- Two solutions were prepared by dissolving 34 grams AgN03 (0.20 mole), 30 grams Cd(NO3~2.4H2O ~0.097 mole) and 0.10 gram Zn~CH3COO)2.2H2O
~o.aoo46 mole) in 100 milliliteTs of doubly distillled water, and 25.4 grams of 87.4% analytical reagent grade KOH (0.396 mole3 in 100 milliliters of distilled water~ Both solutions were rapidly and simultaneously added to lQ0 milliliters of Yigorously stirred doubly distilled water. Then 400 milliliters of additional water were added to suspend the gelatinous precipitate, and 1000 milliliters o~ Cabot Cab-O-Sil* M-5 (a fumed silica) and sufficient water to maintain fluidity and adjust the total volume to 1800 milliliters were added, After 2 hours of further stiTring at room `
temperature, the suspension was allowed to settle 24 hours in the dark at 4C, The SupeTnatant) with a pH of 6.5, was then decanted and the pTe-cipitate removed rom the rest of the solution by vacuum filtration. The ilt~r cake, ater washing with 2000 milliliters of distilled wat~r, was calcined in air at 250C ~or 20 hours. The resulting solid was cooled to room temperature in a vacuum desiccator, and then crushed and sieved to yield a 5a 80 mesh fraction. This composition analyzed as containing 53,7% SiO2, 30.1% Ag, 14.S% Cd, 150 ppm Zn, and 0.4% K. Powder x-Tay diffraction indicated that Ag, Cd(OH)2 and 2 types of Cd2O(OH~2 crystal~
lites exhibiting sharp diffraction lines were present.
A~out 6.5 grams of this material were placed in a 0.924 cm i.d. by 28 cm reactor tube. The tub~ was heated under 201 psig hydrogen flowing at 750 SCCM from 24C to 133C in the course of 30 minutes. At the end of the period, one pa~t acrolein in 40 parts .
*Trademark ,: , , " . , "
10~37S~7 hydrogen replaced the pure hydrogen stream. Table XIV summarizes the reactor conditions and the resultant composition of the : ;
products collected in a trap held at -'78C and reactor pressure just down stream from the catalyst bed. ¦
On powder X-ray diffraction exam.ination ~.he used catalyst exhibited broad lines at 2.36, 2.04, 1.44, 1,23 A with broad back ~:~
reflection lines of medium intensity. These lines are ascribed ~
to an ~-phase silver-cadmium-zinc alloy with an average co~sition ~ ;;
of 67.46% Ag, 32.51% Cd and 0.03% ~n on silica, although the form of the zinc is not definitely known.
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~ 3759~7 EXAMPLE XV :', ~ ,; ,~, ; ., ~
Two solutions were prepared by dissolving 34 grams AgNO3 (0.20 mole~
30 grams Cd~NO3)2.4H20 (0.097 le) and o.sn gram Zn(CH3COO)2.2H2O t0-0023 `~
mole) in 100 milliliters of distilled water, and 25.6 grams of 87.4%
analytical reagent grade KO}I ~0,399 mole) were dissolved in 100 milliliters of distilled water. Both solutions were rapidly and simultaneously added to 100 milliliters of vigorously stirred distilled water. After 400 milliliters of additional water were added to suspend the gelatinous pTe-cipitate, 100 milliliters of Cab-O-Sil* M-5 ~a fumed silica) and sufficient -~
~ater to maintain fluidity and bring the total volume to 1800 milliliters were added. After 2 hours of further stirring at room temperature, the suspension was allowed to settle 24 hours in the dark at 4C. The super-natant, with a pH of 6.5, was then decanted and the precipltate removed rom the rost o the solution by vac~lm filtratlon~ The filt~r cako, a~ter washing with 2000 ~llliliters of distilled water, was calcined in a~r at 250C for 20 hours. The resulting solid was cooled to room tem-peratureJ and crushed and sieved to yield a 50-80 mesh fraction. This material by bulk analytical techniques contalned 51.3~ SiO2, 20.8% Ag, 13.3% Cd, 210 ppm Zn, and 0.6% K Powder X~ray diffraction indîcated 2Q that Ag, Cd(OH~2, and CdO crystallites exhibiting sharp diffraction lines were present~
About 3~36 grams were placed in 0.55 cm i~d~ by 28 cm reactor tube~ The reactor was heated under 209 psig hydrogen flowing at 750 SCCM
from 23C to 125C in 30 minutes. After an additional six minutes, 1 part acrolein in 40 parts hydrogen replaced the pure hydrogen.
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Table XV summarizes various reactor conditions and the ': .
. resultant compo~ition of the liquid products collected in a trap maintained at -78C and reactor pressure. The used oatalyst, by powder X-ray diffraction, had broad lines ascribed to the a-phase AgCd alloy on silica. These alloys had an average composition of .~ 60.959% ~g, 38.797~ Cd, 0.062~ ~n. ~hese were no direct evidence as to the form of the zinc, although under the hydrogenation , conditions it was probable that the zinc had been reduced and ~ il hence alloyed with the silver-cadmium.
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, 1~8759 7' EXAMPLB XVI
Th~o solutions were prepar.,d by dissolving 29.73 grams AN0 .175 molel, 23.14 grams Cd(N03~2.4H20 ~0.075 mole!, and 14.87 grams Zn(N03)2.6H20 ~0.050 mole) in 160 milliliters of distilled water, and 27.3 grams of 87.4% analytical reagent grade KOH ~0.425 mole) in 160 milliliters ;~
distilled water. Both solutions were simultaneously added to 200 milli-liters of vigorously stirred distilled water About 500 milliliters of Cab-O-Sil* M-5 (a funed silica) were then added, along with sufficient additional water to maintain fluidity. The final volume was adjusted to I 10 20QO milliliters by addition of distllled water, and the mixture was stirr0d '~ at Ioom temperature for an additional two hours~ The precipitate was sepaxated from the supernatant KN03 solution by vacuum filtration, and wash~d with 2000 milliliters of distilled water. After partially air drying ~or 18 hours, the ilter cake was rcmoved and placed in an oven and calclned in air at 250C ~or 20 hours. The composition wns crushed and sieved to yield a 50-80 mesh raction. Chemical analysis indicated a content o 39.q% SiO2, 35 8% Ag, 13.3% Cd, 5.3% Zn, and 0 3% K On powder ;~
X ray diffraction examination, weak sharp lines were observed at 2.35, o 20,4, 1.44, and 1.23 A, with a very weak but sharp back reflection pattern.
2Q It was concluded that CdO and Ag crystallites were present. Zinc species were not spe.cifically identified.
A 2.62 gxams quantity of this material was placed in a 0~55 cm i~d. by 28 cm reactor tube. Over the course of one hour the temperatuxe was increased fIom 18 C to 125C under 198 psig hydxogen flowing at 750 SCCI~. hter this period one ,~
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,part acrolein in 40 parts hydrogen replaced the~pure hydrogen~
: ,stream. Table XVI summarizes various reactor condition9 and the resultant composition of the liquid prvducts collected in a trap ,~
held at -78C and reactor pressure. ~.
i The ~sed catalyst on powder X-ray diffractlon examinatlon - '3had broad lines, indicative of -phase AgCdZn alloy, at 2.36, 2.04, o }.44, and 1.23 A, with a very weak back reflection pattern.
Chemical analysis indicated the presence of a 65. 8~ Ag, 24.4% Cd, 9.7~ Zn alloy on the silica. ZnO, AgZn, and Zn lines were not .. . .
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J Two solutions were prepared by dissolving 34.1 grams AgN03 ;~
~0 200 ~ole)~ 60.2 grams CdtNO3)2.4H2O (0.195 mole) and 4.0 grams ZntN03)2.
6H2O (0.0135 mole~ in 100 milliliters of distilled water, and 39.70 grams ;`
~- 87.4% analytical reagent grade KOH (0.618 mole) in 100 milliliters of distilled water. The solutions were rapidly and simultaneously added to ~`
200 milliliters of vigorously stirred distilled water. The volume was ~; increased to 1000 milliliters with additional distilled water, and the suspension was stirred for 30 minutes~ The pH of ~he supernatant phase was 6.5. About 500 milliliters of Cab-O-Sil* M-5 (a fumed silica) were added along with sufficient water to maintain fluidity and to adjust the . . -, , ~
; volume to 1800 milliliters. After 2 hours of stirring, vacuum filtration was used to form a filtor c~ke which wus wushed with 2000 milllliters of . ,:
' distilled water. The muterlal was calcin0d in air ut 200C or 65 hours, cooled in a vacuum desiccator to room temperature, and crushed and sieved ~``to yield a 50_80 mesh fraction. The composition analyzed as containing 28.9% SiO2, 36.7% Ag, 30.3% Cd, 1.2% Zn and 0.1% K. Powder X-ray di~
ffraction examination indicated that CdO and some Ag crystallites were `~the principle species identifiable by medium broad lines at 2.34, 2.04, "
1.23 A with a broad but very weak back reflection pattern. ; ;
A 3,08 grams quantity of catalyst was charged into a 0.55 cm i~d. by 28 cm reactor tube Under 490 psig hydrogen flowing at 1400 SCCM ~;
the catalyst was heated over the course of 48 minutes from 19C to 125C, at which point the hydrogen was changed to a stream of one part acrolein ~i and 109 parts hydrogen. Table XVII -`~
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li summarizes various reactor conditions and the resultant ..
' composition of the liquid products collected in a trap held at -78~C and reactor pressure.
The used catalyst on powder X-ray diffraction exhibited sharp lines at 2.41, 2.36, 2.09, 1.66, 1.48, 1.26 A. It i appeared that principally y and ~ith some ~-phase AgCdZn alloy i was present on the silica. Chemical analysis indicated that .
~ these alloys had an average composition of 53.66% Ag, 44.59% Cd,~
I~ and 1.75~ Zn.
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EXhMPLE XVIII
Two solutions were prepared by dlssolving 33.97 grams AgN03 ~Q,20 molel 92,54 grams Cd(N03)2~4H20 (0.300 ~ole) and 5.05 grams Zn ~03)2 6H20 ~0.017 ~ole) in 100 milliliters of 99DC distilled water, and 53.7~ grams of 87.0% analytical reagent grade KOH (0 834 mole) were dissolved in 100 milliliters of 99C distilled water. Bo~h solutions were rapidly and simultanesusly added to vigorously stirred 99C distilled water, followed by the addition of sufficient water to adjust the volume of the ~; mixture to lQOO milliliters. After 30 minutes of stirring, the pH of the ;~
supernatant was 7Ø About 500 milliliters of Cab-O-Sil~ ~-5 ta fumed silica) and sufficient water to maintain fluidity were added, and the volume was ad~usted to 1800 milliliters with additional distilled wster. The supernatant solution was removed by vacuum filtration, the ~ilter cake i was washed with 3000 millillters of dlstilled watcr. The material was calcined ~or 20 hours at 200C in air, and crushed and sieYed to yleld a 50_80 mesh fraction. This material analyzed as containing 17.9% SiO, ~ ;
28,9% Ag, 39.3% Cd and 1.3% Zn. Powder X-ray diffraction lines indicated ~;
~; Ag, CdO, Cd(OH)2 and some zinc oxide phase were present.
A 6.07 gram quantity of the catalyst was charged to a reactor tube Q,~25 cm i.d. by 28 cm long. With the catalyst under 500 psig hydrogen ~lowing at 1500 SCCM, the temperature of the reactor was increased ;~
from 20C to 250C, malntained at 250C for 15 minutes, nnd then cooled to 125C over a total period of 1.2 hours. After an additional several ;~
minutes, one part acrolein in 111 parts hydrogen was introduced in the reactor. Table XVIII
*T~ademark `
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,.,-., , ¦.1 summarizes various reactor conditions and the resultant .
~i composition of the liquid products co:Llected in a trap held at -78C and reactor pressure. The used catalyst had mainly ~ phase and some ~ and E- phase AgCdZn alloys present on the ¦ : I
ilsilica. The average alloy composition was 41.58% Ag, 56.55% Cd ¦ ~1 and 1.87% Zn.
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T~o solutions were prepared by dissolving 33.97 grams AgN03 ~0.2Q mole), 61~70 grams Cd(N03)2.4H20 ~0~20 mole) and 5.95 grams Zn(N03)2.6H20 (0 020 mole) in 100 milliliters of distilled water, and 41 28 grams of 87~0 analytical reagent grade KOH in 100 milliliters of distilled ~ater. Both solutions were added rapidly and simultaneously to 2QO milliliters of 98C vigorously stirred distilled water. The volume was ;~
then increased to 1000 milliliters with more water, and after 30 minutes of stiTring the pH was 6.5. About 500 milliliters of Cab-O-Sil* M-5 (a fumed silica) were added with sufficient water to maintain fluidity and to adjust the total volume to 1800 milliliters. The precipitate was separated rom the supernatant by vacuum filtration. The filt~r cake was washed with 3000 millillters of dlstilled water and calcined in air at 20ac or 20 hours. Ater cooling in a vacuum desiccator to room temperature, the catalyst precursor was crushed and screened to yield a 50-80 mesh fraction. Analysis indicated a bulk composition of 19.6% SiO2, 33.7% Ag, 37,7% Cd and 1.9% Zn.
A 6,13 gram quantity of the composition was placed in a 0.925 ;;
cm i.d. by 28 cm reactor tube. With the catalyst precursor under 509 psig hydrogen flowing at 1500 SCCM, the temperature was increased from 19C to 250C, held at 250C for 15 minutes, and cooled to 125C over a total 1.4 hours. After several m~nutes, one part acrolein in 113 parts hydTogen was introduced, Table XIX su~marizes various reactor conditions and the resultant composition of the liquid products collected in a trap held at - r78C and reactor pressure. The used catalyst had a nit~ogen BET
surface area of 6.6 m2!gram. Analysis indicated an average ~Trademark .
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AgCdZn alloy ccmposition of 45.98% Ag, 51.43% Cd, and 2.59% Zn on ;~
.silica. Powder X-ray diffraction ana.lysis indicat~s the presence of y with and f-phase AgCdZn on SiO2.
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EXAMPLE XX
Two solutions were prepared by dissolving 50,96 grams AgNO3 C 30 mole~, 61 69 grams Cd(NO3~2,4H2O (0.20 mole~ and 5.95 grams ; ; ;
Zn(NO3)2.6H2O (0.02 le) in 100 milliliters of distilled water, and 47.73 grams of 87.0% analytical reagent grade KOH ~0.74 mole~ in 100 milliliters , :
of distilled water. Both solutions were rapidly and simultaneously added ~ :
to 200 milliliters of distilled water. The mixture after 30 minutes of stirring had a supernatant with a pH of 6.5. 500 milliliters of Cab-O-Sil*
M-5 ~a fumed silica) was added with sufficient water to maintain fluidity and to adjust the total volume to 1800 milliliters, The precipitate was separated from the supernatant solution. This material was then ca}cined `
in air at 200 C for 20 hours, and crushed and sieved to yield a 50-80 mesh fraction. The composition contained 16~2% SiO2, 43.1% Ag, 35.6~ Cd, and 1.6% Zn.
A 6.80~ gram quantity of this catalyst precursor wer~ placed in a 0,925 cm i~d~ ~y 29 cm reactor tu~e. ~ith the catalyst precursor under 50Q psig hydTogen ~99~995%) flowing at 1500 SCCM, the reactor was heated from 19C to 250C for 15 minutes, and cooled to 125C One part acTolein in 112 parts hydrogen was then substituted for the hydTogen.
Table XX summarizes various reactor conditions and the resultant composition i~ ;
o the liquid products collected in a trap held at -78C and reactor psossure. The used catalyst had a nitrogen BET surface area of 32.4 m /gram.
Analysis indicated a AgCdZn alloy with an average composltion of 53~7% ~; `
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Ag~ 44.3% Cd) and 2,0% Zn on the silica, which on powder X~ray diffraction `
examination revealed a,y and E-phase lines, : - -*Trademask '~"
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This Example illustrates the low conversions and low yields o~tained vhen a silver~cadmium-zinc alloy catalyst not in accoTdance with ;
the present invention is not for~ed by coprecipitation of corresponding ~alts and does not include a carrier substrate.
A mixture of 16.5 grams 99.999% metallic zinc (200 mesh~, 10.1 grams 99.999% silver needles ~200 mesh) and 11.8% grams 99.999% cadmium ~ powder ~20a mesh) were introduced into a lt2 inch O.D" Amersil* T08 i quartz tube and pumped down to 5 x 10-5 torr. Two psig 99.~99% H2 was introduced and the temperature increased to 400C. The pressure was again reduced to S x 10 5 torr, a fresh charge of 2 psig 99 999% H2 admitted, the pressure again reduced to 10 4 torr, 99.999% H2 readmitted to 2 psig, and held at 400C or 1 hour. The pressure was reduced to 5 x 10 5 torr ;~
and the tube was sealed with a torch. The tube was heated to 800C for 1 hour and cooled, The resulting ingot was fllod with a clean and degrensed *teel file to yield fillngs. These analyzed AS containing 34,2go Ag, 27.0% ~ ;
Cd, and 41~4% Zn. On powder X-ray diffraction, the material was found to ~ ;
be a highly crystalline composition which was comprised of Ag~n3 and AgCd.
About 19,6 grams of these filings were treated with 2 liters of ~ ~;
4 normal KOH solution for 24 hours under a nitrogen atmosphere. The solution above the filings was then replaced by 2 liters of 6N KOH solution ~ ~
and re1uxed for 72 hours under a nitrogen at sphere. After cooling to ;Toom temperature, the metal composition was rinsed with distilled water until the pH of the rinse water was 6.5. The catalyst was placed in a ;
0~55 cm i,d.
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, by 28 cm reactor tube. ~he volume of the catalyst bed was Z.5 i cm3. The reactor was then placed under 500 psig hydrogen ~lowing at 1500 SCCM and the temperature raisl_d from 23C to 200C, held ¦
at 200C for 20 minutes, and cooled t~ 125C. After an additional period of 6 minutes the 99.999% hydrogen was ¦~
replaced by cne part acrolein in 111 !parts 99.995% hydrogen.
Table XXI summarizes various r,eactor conditions and the : ¦
I resultant composition of the liquid products collected in a Ii trap held at -78C and reactor pressure.
il The used catalyst had a surface area of 0.51 M2/gram and ! had a composition of 52.8% Ag, 48.4% Cd, and 1.1% Zn~ No K was !
,~ detected. Powder X-ray diffraction indicated that it was ; comprised mostly of Y-phase AgCdZn alloy with ~ome ~ and ~-phase al80 present. A high degree of order was observed.
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This Example illustrates the conversion and yields obtained when a silver-cadmium~zinc alloy catalyst contains copper metal.
Tho solutions were prepared by dissolving 34 grams AgNU3 Lo.20 mole), 30 grams Cd~N03)2.4H20 (0.97 mole), 0.10 grams Zn (~l3C00)2. ~ ;
2H20 (O.OOQ46 mole) and 0.10 grams Cu(N03~2~3H20 (0.00041 mole) in 100 milliliters of distilled wate~, and 25.45 grams of 87.4 analytical reagent grade KOH C0.3964 le) in 100 milliliters of distilled water. Both solutions were added rapidly and simultaneously to 100 milliliters of ~ ;
vigorously stirred distilled water. The volume was then increased to 1000 milliliters with the addition of more water, and after one hour of stirring, the pH of the supem atant was found to bc 6.5. About 1000 ~illiliters o~ Cab~O~Sil~ M-5 ~a fumed silica) and su~ficient water to adju~t the tot~l volume to 1800 n~illiliters were added. ~fter 4 hours of stirring the precipitate was separated from the supernatant solu~ion. ~le material was calcined in air at 250C for 20 hours~ and washed and sieved to yield a 2Q-80 mesh fraction. Bulk chemical analysis indicated that this material contained 52 8% SiO2, 29 7% Ag, 12.7% Cd, 0,7% K, 370 ppm Cu and 550 ppm Zn, Powder X~ray diffraction examination revealed pri~cipally CdO.
A 7,45 gram quantity of this romposition was changed to a 0,925 cm i.d. by 28 cm reactor tube. With the catalyst precursor under 485 psig hydrogen flowing 1500 SCCM, the reactor tube was heated over the course of one hour from 21 to 125C. The hydrogen flow was replaced with a stream of one part acrolein in 108 parts hydrogen.
*Trademark -75_ ~75~
~I Table XXII sU~rizes various reactor conditions and the ,¦ resultant composition of the liquid products collec~ed in a trap held at -78C and reactor pressure.
Powder X-ray diffraction examination of the used catalyst~ ' revealed an -phase AgCdCuZn alloy and a silver rich ~-phase 1~:
. 1, Ag,Cd(ZnCu~ alloy on silica. Relativel~ broad split lines were !
found at 2.37, 2.05, 1.45, 1.44, 1.24, 1.23 A, with a weak broad ' :
back reflection also showing splitting. The average composition, !
''I by bulk analysis techniques, was 69.90% Ag, 29.89~ Cd, 0.12~ Zn, Ii O.0996 CU.
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EXAMPLE XII ! ;! -: This Example illustrates thc l~wer conversions obtained when a silver-cadmium catalyst not in accordance with the present invention contains coprecipitated silver-cadmium alloy without a carrier substrate.
Two solutions were prepared by dissolving 34.0 grams AgNO3 (0.200 mole~ and 41.2 grams Cd(NO3)2 4H2O ~0.134 mole) in ; 100 milliliters of distilled water, and 30.12 grams of 97.0%
i analytical reagent grade KOH (0.537 mole) in 100 milliliters of I distilled ~ater. Both solu~ions were added simultaneously and in a rapid dropwise fashion to 400 milliliters of vigorously stirred distilled water. ~he pH was adjusted to 7.0 with ~OH or Xl~03 I as needed, and the volume was increased with distilled water to , 2000 milliliters. The suspension was allowed to settle at 4C, j' protected from light. The clear supernatant liquid was~drawn off and fresh distilled water was added to adjust~the volume to~
2000 milliliters. Il The solids were recovered from the solution by vacuum filtration, washed with 2000 milliliters of distilled water, and calcined in air at 200C for 20 hours. After cooling in a vacuum , desiccator, the material was crushed and sieved to~yield a -I 50-80 mesh fraction. Chemical analysis indicated that the bulk `I material was 55.6% Ag and 43.4~ Cd.
, A 6.83 yram quantity of thio material was~placedjin a ; 0.55 cm i.d. by 28 cm reactor tube. sOver a period o~ twc hours.
, the catalyst was treated with 501 psig hydrogen }lowing at }500 ¦
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SCCM heated from 24 to 250C, held at 2S0C for 15 minutes, and : cooled to 125C. At this time, 1 part acrolein in 111 parts . hydrogen replaced the pure hydrogen f:low stream.
Table XII summarizes various reactor conditions and the i, resultant composition of the liquid products collected in a trap ; held at -78C and reactor pressure. The used catalyst had a nitrogen BET surface area of 0.15 m2/gram, and was a mixture , of ~,y with some E-phase silver-cadmium alloys. I
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EXAMPLE XIII -This Example illustrates the conversions and yields obtained t~ :
when a silver-cadmium alloy catalyst contains copper metal, ~ ~
Two solutions were prepared by dissolving 34.00 grams AgN03 ~ ~ ;
CO,20015 mole~, 30,00 grams Cd(N03)2.4H20 (0.09725 mole), and 0.60 gram Cu(N03)2.3H20 ~0~00248 mole) in 100 milliliters of distilled water, and 25.70 grams of 87.4% analytical reagent grade KO~I ~0.4003 mole) in 100 milliliters of distilled water. Both solutions were added rapidly and simultaneously to 100 milliliters of vigorously stirred distilled water. ;~
After the formation of the blackish gelatinous precipitate, the volume of the system was adjusted to lOOO milliliters with aclditional distilled water. The pH of the supernatant was 6~5, lOOO milliliters of Cab-O-Sil*
M-S (a umed silica) and sufficient water to adjust the total volume to 18QQ milliliters were added~ The precipitate was removed rom the super-na~ant solution by vacuum filtration and washed with 2Q~O milllliters of distilled water. The solid was then calclned in air at 250C ~or 20 hours. The material was crushed and sieved to yield a 50-80 mesh fruction.
..
The composition analyzed as containing 53.7% SiO2, 26.9% Ag, 16.9% Cd, 0.5% K, and 0,8% Cu. Powder X-ray diffraction examination identified ~; 2Q only lines indicating CdO.
A 7,72 grams quantity of this material was placed in a 0.925 cm i.d. by 29 cm reactor tube. With 500 psig hydrogen flowing over the ;~
catalyst precusor at 1500 SCCM, the temperature of the reactor was increased from 19C to 200C, held at 200C for 15 minutes, and cooled to 125C. The hydrogen stream was replaced ~T~adem~k ::
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-~08759'7 , `~ .
' with 1 part acrolein in 110 parts hydrogen.
~able XIIIsummarizes various reactor conditions and the resultant composition of liquid products collected in a trap held at -78C and reactor pressure. q~he used catalyst had a ,! surface area of 47.8 m2/gm~ and exhibited a silver rich ~-phase I AgCd(Cu) alloy on silica with an averaye composition of 60.31%~
Ag, 37.89~ Cd and 1.79% Cu. ~; ' In the same manner, a second catalyst was prepared with a Jl s i , ~
. bulk content of 54.4~ SiO2, 31.6% Ag, 14.1~ Cd, and about 660 ppm !
. , cu.
Table XIII-A gu~rizes various reactor conditions and the resultant composition of the liquid products collected in a trap ;held at 78~C and reactor pressure employing the second catalyst.
; The used catalyst, on powder X-ray diffraction examination, o ~ ~
~ exhibited sharp lines at 2.36, 2.04, 1.44, 1.23 A, with a-strong ~ ~ ~
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sharp back re~lection pattern eviden~. Chemical analysis ~ indicated a silver rich ~i-phase AgCd(Cu) alloy of 69.0~ Ag, ,, . ~.
30.8% Cd, and 0.14~ Cu average composition on the silica. ~
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EXAMPLE XIV
- Two solutions were prepared by dissolving 34 grams AgN03 (0.20 mole), 30 grams Cd(NO3~2.4H2O ~0.097 mole) and 0.10 gram Zn~CH3COO)2.2H2O
~o.aoo46 mole) in 100 milliliteTs of doubly distillled water, and 25.4 grams of 87.4% analytical reagent grade KOH (0.396 mole3 in 100 milliliters of distilled water~ Both solutions were rapidly and simultaneously added to lQ0 milliliters of Yigorously stirred doubly distilled water. Then 400 milliliters of additional water were added to suspend the gelatinous precipitate, and 1000 milliliters o~ Cabot Cab-O-Sil* M-5 (a fumed silica) and sufficient water to maintain fluidity and adjust the total volume to 1800 milliliters were added, After 2 hours of further stiTring at room `
temperature, the suspension was allowed to settle 24 hours in the dark at 4C, The SupeTnatant) with a pH of 6.5, was then decanted and the pTe-cipitate removed rom the rest of the solution by vacuum filtration. The ilt~r cake, ater washing with 2000 milliliters of distilled wat~r, was calcined in air at 250C ~or 20 hours. The resulting solid was cooled to room temperature in a vacuum desiccator, and then crushed and sieved to yield a 5a 80 mesh fraction. This composition analyzed as containing 53,7% SiO2, 30.1% Ag, 14.S% Cd, 150 ppm Zn, and 0.4% K. Powder x-Tay diffraction indicated that Ag, Cd(OH)2 and 2 types of Cd2O(OH~2 crystal~
lites exhibiting sharp diffraction lines were present.
A~out 6.5 grams of this material were placed in a 0.924 cm i.d. by 28 cm reactor tube. The tub~ was heated under 201 psig hydrogen flowing at 750 SCCM from 24C to 133C in the course of 30 minutes. At the end of the period, one pa~t acrolein in 40 parts .
*Trademark ,: , , " . , "
10~37S~7 hydrogen replaced the pure hydrogen stream. Table XIV summarizes the reactor conditions and the resultant composition of the : ;
products collected in a trap held at -'78C and reactor pressure just down stream from the catalyst bed. ¦
On powder X-ray diffraction exam.ination ~.he used catalyst exhibited broad lines at 2.36, 2.04, 1.44, 1,23 A with broad back ~:~
reflection lines of medium intensity. These lines are ascribed ~
to an ~-phase silver-cadmium-zinc alloy with an average co~sition ~ ;;
of 67.46% Ag, 32.51% Cd and 0.03% ~n on silica, although the form of the zinc is not definitely known.
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~ 3759~7 EXAMPLE XV :', ~ ,; ,~, ; ., ~
Two solutions were prepared by dissolving 34 grams AgNO3 (0.20 mole~
30 grams Cd~NO3)2.4H20 (0.097 le) and o.sn gram Zn(CH3COO)2.2H2O t0-0023 `~
mole) in 100 milliliters of distilled water, and 25.6 grams of 87.4%
analytical reagent grade KO}I ~0,399 mole) were dissolved in 100 milliliters of distilled water. Both solutions were rapidly and simultaneously added to 100 milliliters of vigorously stirred distilled water. After 400 milliliters of additional water were added to suspend the gelatinous pTe-cipitate, 100 milliliters of Cab-O-Sil* M-5 ~a fumed silica) and sufficient -~
~ater to maintain fluidity and bring the total volume to 1800 milliliters were added. After 2 hours of further stirring at room temperature, the suspension was allowed to settle 24 hours in the dark at 4C. The super-natant, with a pH of 6.5, was then decanted and the precipltate removed rom the rost o the solution by vac~lm filtratlon~ The filt~r cako, a~ter washing with 2000 ~llliliters of distilled water, was calcined in a~r at 250C for 20 hours. The resulting solid was cooled to room tem-peratureJ and crushed and sieved to yield a 50-80 mesh fraction. This material by bulk analytical techniques contalned 51.3~ SiO2, 20.8% Ag, 13.3% Cd, 210 ppm Zn, and 0.6% K Powder X~ray diffraction indîcated 2Q that Ag, Cd(OH~2, and CdO crystallites exhibiting sharp diffraction lines were present~
About 3~36 grams were placed in 0.55 cm i~d~ by 28 cm reactor tube~ The reactor was heated under 209 psig hydrogen flowing at 750 SCCM
from 23C to 125C in 30 minutes. After an additional six minutes, 1 part acrolein in 40 parts hydrogen replaced the pure hydrogen.
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Table XV summarizes various reactor conditions and the ': .
. resultant compo~ition of the liquid products collected in a trap maintained at -78C and reactor pressure. The used oatalyst, by powder X-ray diffraction, had broad lines ascribed to the a-phase AgCd alloy on silica. These alloys had an average composition of .~ 60.959% ~g, 38.797~ Cd, 0.062~ ~n. ~hese were no direct evidence as to the form of the zinc, although under the hydrogenation , conditions it was probable that the zinc had been reduced and ~ il hence alloyed with the silver-cadmium.
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, 1~8759 7' EXAMPLB XVI
Th~o solutions were prepar.,d by dissolving 29.73 grams AN0 .175 molel, 23.14 grams Cd(N03~2.4H20 ~0.075 mole!, and 14.87 grams Zn(N03)2.6H20 ~0.050 mole) in 160 milliliters of distilled water, and 27.3 grams of 87.4% analytical reagent grade KOH ~0.425 mole) in 160 milliliters ;~
distilled water. Both solutions were simultaneously added to 200 milli-liters of vigorously stirred distilled water About 500 milliliters of Cab-O-Sil* M-5 (a funed silica) were then added, along with sufficient additional water to maintain fluidity. The final volume was adjusted to I 10 20QO milliliters by addition of distllled water, and the mixture was stirr0d '~ at Ioom temperature for an additional two hours~ The precipitate was sepaxated from the supernatant KN03 solution by vacuum filtration, and wash~d with 2000 milliliters of distilled water. After partially air drying ~or 18 hours, the ilter cake was rcmoved and placed in an oven and calclned in air at 250C ~or 20 hours. The composition wns crushed and sieved to yield a 50-80 mesh raction. Chemical analysis indicated a content o 39.q% SiO2, 35 8% Ag, 13.3% Cd, 5.3% Zn, and 0 3% K On powder ;~
X ray diffraction examination, weak sharp lines were observed at 2.35, o 20,4, 1.44, and 1.23 A, with a very weak but sharp back reflection pattern.
2Q It was concluded that CdO and Ag crystallites were present. Zinc species were not spe.cifically identified.
A 2.62 gxams quantity of this material was placed in a 0~55 cm i~d. by 28 cm reactor tube. Over the course of one hour the temperatuxe was increased fIom 18 C to 125C under 198 psig hydxogen flowing at 750 SCCI~. hter this period one ,~
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,part acrolein in 40 parts hydrogen replaced the~pure hydrogen~
: ,stream. Table XVI summarizes various reactor condition9 and the resultant composition of the liquid prvducts collected in a trap ,~
held at -78C and reactor pressure. ~.
i The ~sed catalyst on powder X-ray diffractlon examinatlon - '3had broad lines, indicative of -phase AgCdZn alloy, at 2.36, 2.04, o }.44, and 1.23 A, with a very weak back reflection pattern.
Chemical analysis indicated the presence of a 65. 8~ Ag, 24.4% Cd, 9.7~ Zn alloy on the silica. ZnO, AgZn, and Zn lines were not .. . .
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J Two solutions were prepared by dissolving 34.1 grams AgN03 ;~
~0 200 ~ole)~ 60.2 grams CdtNO3)2.4H2O (0.195 mole) and 4.0 grams ZntN03)2.
6H2O (0.0135 mole~ in 100 milliliters of distilled water, and 39.70 grams ;`
~- 87.4% analytical reagent grade KOH (0.618 mole) in 100 milliliters of distilled water. The solutions were rapidly and simultaneously added to ~`
200 milliliters of vigorously stirred distilled water. The volume was ~; increased to 1000 milliliters with additional distilled water, and the suspension was stirred for 30 minutes~ The pH of ~he supernatant phase was 6.5. About 500 milliliters of Cab-O-Sil* M-5 (a fumed silica) were added along with sufficient water to maintain fluidity and to adjust the . . -, , ~
; volume to 1800 milliliters. After 2 hours of stirring, vacuum filtration was used to form a filtor c~ke which wus wushed with 2000 milllliters of . ,:
' distilled water. The muterlal was calcin0d in air ut 200C or 65 hours, cooled in a vacuum desiccator to room temperature, and crushed and sieved ~``to yield a 50_80 mesh fraction. The composition analyzed as containing 28.9% SiO2, 36.7% Ag, 30.3% Cd, 1.2% Zn and 0.1% K. Powder X-ray di~
ffraction examination indicated that CdO and some Ag crystallites were `~the principle species identifiable by medium broad lines at 2.34, 2.04, "
1.23 A with a broad but very weak back reflection pattern. ; ;
A 3,08 grams quantity of catalyst was charged into a 0.55 cm i~d. by 28 cm reactor tube Under 490 psig hydrogen flowing at 1400 SCCM ~;
the catalyst was heated over the course of 48 minutes from 19C to 125C, at which point the hydrogen was changed to a stream of one part acrolein ~i and 109 parts hydrogen. Table XVII -`~
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li summarizes various reactor conditions and the resultant ..
' composition of the liquid products collected in a trap held at -78~C and reactor pressure.
The used catalyst on powder X-ray diffraction exhibited sharp lines at 2.41, 2.36, 2.09, 1.66, 1.48, 1.26 A. It i appeared that principally y and ~ith some ~-phase AgCdZn alloy i was present on the silica. Chemical analysis indicated that .
~ these alloys had an average composition of 53.66% Ag, 44.59% Cd,~
I~ and 1.75~ Zn.
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EXhMPLE XVIII
Two solutions were prepared by dlssolving 33.97 grams AgN03 ~Q,20 molel 92,54 grams Cd(N03)2~4H20 (0.300 ~ole) and 5.05 grams Zn ~03)2 6H20 ~0.017 ~ole) in 100 milliliters of 99DC distilled water, and 53.7~ grams of 87.0% analytical reagent grade KOH (0 834 mole) were dissolved in 100 milliliters of 99C distilled water. Bo~h solutions were rapidly and simultanesusly added to vigorously stirred 99C distilled water, followed by the addition of sufficient water to adjust the volume of the ~; mixture to lQOO milliliters. After 30 minutes of stirring, the pH of the ;~
supernatant was 7Ø About 500 milliliters of Cab-O-Sil~ ~-5 ta fumed silica) and sufficient water to maintain fluidity were added, and the volume was ad~usted to 1800 milliliters with additional distilled wster. The supernatant solution was removed by vacuum filtration, the ~ilter cake i was washed with 3000 millillters of dlstilled watcr. The material was calcined ~or 20 hours at 200C in air, and crushed and sieYed to yleld a 50_80 mesh fraction. This material analyzed as containing 17.9% SiO, ~ ;
28,9% Ag, 39.3% Cd and 1.3% Zn. Powder X-ray diffraction lines indicated ~;
~; Ag, CdO, Cd(OH)2 and some zinc oxide phase were present.
A 6.07 gram quantity of the catalyst was charged to a reactor tube Q,~25 cm i.d. by 28 cm long. With the catalyst under 500 psig hydrogen ~lowing at 1500 SCCM, the temperature of the reactor was increased ;~
from 20C to 250C, malntained at 250C for 15 minutes, nnd then cooled to 125C over a total period of 1.2 hours. After an additional several ;~
minutes, one part acrolein in 111 parts hydrogen was introduced in the reactor. Table XVIII
*T~ademark `
64~ ~ ~
,.,-., , ¦.1 summarizes various reactor conditions and the resultant .
~i composition of the liquid products co:Llected in a trap held at -78C and reactor pressure. The used catalyst had mainly ~ phase and some ~ and E- phase AgCdZn alloys present on the ¦ : I
ilsilica. The average alloy composition was 41.58% Ag, 56.55% Cd ¦ ~1 and 1.87% Zn.
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T~o solutions were prepared by dissolving 33.97 grams AgN03 ~0.2Q mole), 61~70 grams Cd(N03)2.4H20 ~0~20 mole) and 5.95 grams Zn(N03)2.6H20 (0 020 mole) in 100 milliliters of distilled water, and 41 28 grams of 87~0 analytical reagent grade KOH in 100 milliliters of distilled ~ater. Both solutions were added rapidly and simultaneously to 2QO milliliters of 98C vigorously stirred distilled water. The volume was ;~
then increased to 1000 milliliters with more water, and after 30 minutes of stiTring the pH was 6.5. About 500 milliliters of Cab-O-Sil* M-5 (a fumed silica) were added with sufficient water to maintain fluidity and to adjust the total volume to 1800 milliliters. The precipitate was separated rom the supernatant by vacuum filtration. The filt~r cake was washed with 3000 millillters of dlstilled water and calcined in air at 20ac or 20 hours. Ater cooling in a vacuum desiccator to room temperature, the catalyst precursor was crushed and screened to yield a 50-80 mesh fraction. Analysis indicated a bulk composition of 19.6% SiO2, 33.7% Ag, 37,7% Cd and 1.9% Zn.
A 6,13 gram quantity of the composition was placed in a 0.925 ;;
cm i.d. by 28 cm reactor tube. With the catalyst precursor under 509 psig hydrogen flowing at 1500 SCCM, the temperature was increased from 19C to 250C, held at 250C for 15 minutes, and cooled to 125C over a total 1.4 hours. After several m~nutes, one part acrolein in 113 parts hydTogen was introduced, Table XIX su~marizes various reactor conditions and the resultant composition of the liquid products collected in a trap held at - r78C and reactor pressure. The used catalyst had a nit~ogen BET
surface area of 6.6 m2!gram. Analysis indicated an average ~Trademark .
:
r- ~
, . : , ~ : . .. .
~ '7~
AgCdZn alloy ccmposition of 45.98% Ag, 51.43% Cd, and 2.59% Zn on ;~
.silica. Powder X-ray diffraction ana.lysis indicat~s the presence of y with and f-phase AgCdZn on SiO2.
:, :
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EXAMPLE XX
Two solutions were prepared by dissolving 50,96 grams AgNO3 C 30 mole~, 61 69 grams Cd(NO3~2,4H2O (0.20 mole~ and 5.95 grams ; ; ;
Zn(NO3)2.6H2O (0.02 le) in 100 milliliters of distilled water, and 47.73 grams of 87.0% analytical reagent grade KOH ~0.74 mole~ in 100 milliliters , :
of distilled water. Both solutions were rapidly and simultaneously added ~ :
to 200 milliliters of distilled water. The mixture after 30 minutes of stirring had a supernatant with a pH of 6.5. 500 milliliters of Cab-O-Sil*
M-5 ~a fumed silica) was added with sufficient water to maintain fluidity and to adjust the total volume to 1800 milliliters, The precipitate was separated from the supernatant solution. This material was then ca}cined `
in air at 200 C for 20 hours, and crushed and sieved to yield a 50-80 mesh fraction. The composition contained 16~2% SiO2, 43.1% Ag, 35.6~ Cd, and 1.6% Zn.
A 6.80~ gram quantity of this catalyst precursor wer~ placed in a 0,925 cm i~d~ ~y 29 cm reactor tu~e. ~ith the catalyst precursor under 50Q psig hydTogen ~99~995%) flowing at 1500 SCCM, the reactor was heated from 19C to 250C for 15 minutes, and cooled to 125C One part acTolein in 112 parts hydrogen was then substituted for the hydTogen.
Table XX summarizes various reactor conditions and the resultant composition i~ ;
o the liquid products collected in a trap held at -78C and reactor psossure. The used catalyst had a nitrogen BET surface area of 32.4 m /gram.
Analysis indicated a AgCdZn alloy with an average composltion of 53~7% ~; `
;, , .;
Ag~ 44.3% Cd) and 2,0% Zn on the silica, which on powder X~ray diffraction `
examination revealed a,y and E-phase lines, : - -*Trademask '~"
B
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_ 71 _ lOB759 7 EXAMPLE XXI
This Example illustrates the low conversions and low yields o~tained vhen a silver~cadmium-zinc alloy catalyst not in accoTdance with ;
the present invention is not for~ed by coprecipitation of corresponding ~alts and does not include a carrier substrate.
A mixture of 16.5 grams 99.999% metallic zinc (200 mesh~, 10.1 grams 99.999% silver needles ~200 mesh) and 11.8% grams 99.999% cadmium ~ powder ~20a mesh) were introduced into a lt2 inch O.D" Amersil* T08 i quartz tube and pumped down to 5 x 10-5 torr. Two psig 99.~99% H2 was introduced and the temperature increased to 400C. The pressure was again reduced to S x 10 5 torr, a fresh charge of 2 psig 99 999% H2 admitted, the pressure again reduced to 10 4 torr, 99.999% H2 readmitted to 2 psig, and held at 400C or 1 hour. The pressure was reduced to 5 x 10 5 torr ;~
and the tube was sealed with a torch. The tube was heated to 800C for 1 hour and cooled, The resulting ingot was fllod with a clean and degrensed *teel file to yield fillngs. These analyzed AS containing 34,2go Ag, 27.0% ~ ;
Cd, and 41~4% Zn. On powder X-ray diffraction, the material was found to ~ ;
be a highly crystalline composition which was comprised of Ag~n3 and AgCd.
About 19,6 grams of these filings were treated with 2 liters of ~ ~;
4 normal KOH solution for 24 hours under a nitrogen atmosphere. The solution above the filings was then replaced by 2 liters of 6N KOH solution ~ ~
and re1uxed for 72 hours under a nitrogen at sphere. After cooling to ;Toom temperature, the metal composition was rinsed with distilled water until the pH of the rinse water was 6.5. The catalyst was placed in a ;
0~55 cm i,d.
*Trademark ;;' ~`; ~
- -:
~ -72~
, by 28 cm reactor tube. ~he volume of the catalyst bed was Z.5 i cm3. The reactor was then placed under 500 psig hydrogen ~lowing at 1500 SCCM and the temperature raisl_d from 23C to 200C, held ¦
at 200C for 20 minutes, and cooled t~ 125C. After an additional period of 6 minutes the 99.999% hydrogen was ¦~
replaced by cne part acrolein in 111 !parts 99.995% hydrogen.
Table XXI summarizes various r,eactor conditions and the : ¦
I resultant composition of the liquid products collected in a Ii trap held at -78C and reactor pressure.
il The used catalyst had a surface area of 0.51 M2/gram and ! had a composition of 52.8% Ag, 48.4% Cd, and 1.1% Zn~ No K was !
,~ detected. Powder X-ray diffraction indicated that it was ; comprised mostly of Y-phase AgCdZn alloy with ~ome ~ and ~-phase al80 present. A high degree of order was observed.
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" ~Q~7Sg~7 EXAMPLE XXII ~;~
This Example illustrates the conversion and yields obtained when a silver-cadmium~zinc alloy catalyst contains copper metal.
Tho solutions were prepared by dissolving 34 grams AgNU3 Lo.20 mole), 30 grams Cd~N03)2.4H20 (0.97 mole), 0.10 grams Zn (~l3C00)2. ~ ;
2H20 (O.OOQ46 mole) and 0.10 grams Cu(N03~2~3H20 (0.00041 mole) in 100 milliliters of distilled wate~, and 25.45 grams of 87.4 analytical reagent grade KOH C0.3964 le) in 100 milliliters of distilled water. Both solutions were added rapidly and simultaneously to 100 milliliters of ~ ;
vigorously stirred distilled water. The volume was then increased to 1000 milliliters with the addition of more water, and after one hour of stirring, the pH of the supem atant was found to bc 6.5. About 1000 ~illiliters o~ Cab~O~Sil~ M-5 ~a fumed silica) and su~ficient water to adju~t the tot~l volume to 1800 n~illiliters were added. ~fter 4 hours of stirring the precipitate was separated from the supernatant solu~ion. ~le material was calcined in air at 250C for 20 hours~ and washed and sieved to yield a 2Q-80 mesh fraction. Bulk chemical analysis indicated that this material contained 52 8% SiO2, 29 7% Ag, 12.7% Cd, 0,7% K, 370 ppm Cu and 550 ppm Zn, Powder X~ray diffraction examination revealed pri~cipally CdO.
A 7,45 gram quantity of this romposition was changed to a 0,925 cm i.d. by 28 cm reactor tube. With the catalyst precursor under 485 psig hydrogen flowing 1500 SCCM, the reactor tube was heated over the course of one hour from 21 to 125C. The hydrogen flow was replaced with a stream of one part acrolein in 108 parts hydrogen.
*Trademark -75_ ~75~
~I Table XXII sU~rizes various reactor conditions and the ,¦ resultant composition of the liquid products collec~ed in a trap held at -78C and reactor pressure.
Powder X-ray diffraction examination of the used catalyst~ ' revealed an -phase AgCdCuZn alloy and a silver rich ~-phase 1~:
. 1, Ag,Cd(ZnCu~ alloy on silica. Relativel~ broad split lines were !
found at 2.37, 2.05, 1.45, 1.44, 1.24, 1.23 A, with a weak broad ' :
back reflection also showing splitting. The average composition, !
''I by bulk analysis techniques, was 69.90% Ag, 29.89~ Cd, 0.12~ Zn, Ii O.0996 CU.
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Claims (38)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An improved hydrogenation process for converting an .alpha.,.beta.-olefini-cally unsaturated carbonylic compound into the corresponding allylic alcohol derivative which comprises reacting an .alpha.,.beta.-olefinically unsaturated car-bonylic compound with hydrogen in the vapor phase at a temperature between about 0°C and 300°C and a pressure between about 15 and 15,000 psi in the pre-sence of a catalyst comprising a silver-cadmium alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the alloy exhibits an X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines.
2. A process in accordance with claim 1 wherein the carbonylic compound is acroleln.
3. A process in accordance with claim 1 wherein the carbonylic compound is methacrolein.
4. A process in accordance with claim 1 wherein the carbonylic com-pound is crotonaldehyde.
5. A process in accordance with claim 1 wherein the carbonylic compound is methylvinyl ketone.
6. A process in accordance with claim 1 wherein the carbonylic compound is methylisopropenyl ketone.
7. A process in accordance with claim 1 wherein the molar ratio of hydrogen to carbonylic compound is in the range between about 1 and 1000 to 1.
8. A process in accordance with claim 1 wherein the quantity of carrier substrate in the catalyst is in the range between about 5 and 99.5 weight percent, based on the total catalyst weight.
9. A process in accordance with claim 1 wherein the carrier substrate is alumina.
10. A process in accordance with claim 1 wherein the carrier substrate is silica.
11. A catalyst composition consisting essentially of a silver-cadmium alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1; and wherein the silver-cadmium alloy exhibits an X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines.
12. A catalyst composition in accordance with claim 11 wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.4 and 3 to 1.
13. A catalyst composition in accordance with claim 11 wherein the quantity of carrier substrate in the catalyst is in the range between about 5 and 99.5 weight percent, based on the total catalyst weight.
14. A catalyst composition in accordance with claim 11 wherein the carrier substrate is alumina,
15. A catalyst composition in accordance with claim 11 wherein the carrier substrate is silica.
16. A catalyst composition in accordance with claim 11 wherein the silver-cadmium alloy consists of more than about 50 percent .gamma.-phase silver cadmium crystallites.
17. A catalyst compositiob in accordance with claim 11 wherein the silver-cadmium alloy consists substantially of .alpha.-phase silver-cadmium alloy crystallites, and the X-ray diffraction pattern of the .alpha.-phase silver-cadmium alloy crystallites does not exhibit line splitting.
18. A catalyst composition in accordance with claim 11 wherein the silver-cadmium alloy consists essentially of .alpha.-phase, .gamma.-phase and .epsilon.-phase silver-cadmium alloy crystallites, and the X-ray diffraction pattern of the a phase silver-cadmium alloy crystallite does not exhibit line splitting.
19. A catalyst composition in accordance with claim 11 wherein the silver-cadmium alloy consists essentially of .alpha.-phase and .gamma.-phase silver-cadmium alloy crystallites, and the X-ray diffraction pattern of the .alpha.-phase silver-cadmium alloy crystallites does not exhibit line splitting.
20. An improved hydrogenation process for converting an .alpha.,.beta.,-olefini-cally unsaturated carbonylic compound into the corresponding allylic alcohol derivative which comprises reacting an .alpha.,.beta.,-olefinically unsaturated carbonylic compound with hydrogen in the vapor phase at a temperature between about 0°C
and 300 C and a pressure between about 15 and 15,000 psi in the presence of a catalyst comprising a silver-cadmium-zinc alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the zinc is contained in the alloy in a quantity between about 0.001 and 30 weight percent, based on the total weight of alloy, and wherein the silver-cadmium-zinc alloy exhibits an X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines.
and 300 C and a pressure between about 15 and 15,000 psi in the presence of a catalyst comprising a silver-cadmium-zinc alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the zinc is contained in the alloy in a quantity between about 0.001 and 30 weight percent, based on the total weight of alloy, and wherein the silver-cadmium-zinc alloy exhibits an X-ray diffraction pattern which is substantially free of detectable unalloyed metal crystallite lines.
21. A process in accordance with claim 20 wherein the carbonylic compound is acrolein.
22. A process in accordance with claim 20 wherein the carbonylic compound is methacrolein.
23. A process in accordance with claim 20 wherein the carbonylic compound is crotonaldehyde.
24. A process in accordance with claim 20 wherein the carbonylic compound is methylvinyl ketone.
25. A process in accordance with claim 20 wherein the carbonylic compound is methylisopropenyl ketone.
26. A process in accordance with claim 20 wherein the molar ratio of hydrogen to carbonylic compound is in the range between about 1 and 1000 to 1.
27. A process in accordance with claim 20 wherein the quantity of carrier substrate in the catalyst is in the range between about 5 and 99.5 weight percent, based on the total catalyst weight.
28. A process in accordance with claim 20 wherein the carrier substrate is alumina.
29. A process in accordance with claim 20 wherein the carrier sub-strate is silica.
30. A catalyst composition consisting essentially of a silver-cadmium-zinc alloy on a carrier substrate, wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.1 and 3 to 1, and the zinc is contained in the alloy in a quantity between about 0.001 and 30 weight percent, based on the total weight of alloy; and wherein the silver-cadmium-zinc alloy exhibits an X-ray diffraction pattern which is sub-stantially free of detectable unalloyed metal crystallite lines.
31. A catalyst composition in accordance with claim 30 wherein the atomic ratio of silver to cadmium in the alloy is in the range of between about 0.4 and 2.2 to 1, and the zinc is contained in the alloy in a quantity between about 0.01 and 15 weight percent, based on the total weight of alloy.
32. A catalyst composition in accordance with claim 30 wherein the quantity of carrier substrate in the catalyst is in the range between about 5 and 99.5 weight percent, based on the total catalyst weight.
33. A catalyst composition in accordance with claim 30 wherein the carrier substrate is alumina.
34. A catalyst composition in accordance with claim 30 wherein the carrier substrate is silica.
35. A catalyst composition in accordance with claim 30 wherein the silver-cadmium-zinc alloy consists of more than about 50 percent .gamma.-phase silver-cadmium zinc crystallites.
36. A catalyst composition in accordance with claim 30 wherein the silver-cadmium-zinc alloy consists substantially of a-phase silver-cadmium-zinc alloy crystallites, and the X-ray diffraction pattern of the .alpha.-phase silver-cadmium-zinc alloy crystallites does not exhibit line splitting.
37. A catalyst composition in accordance with claim 30 wherein the silver-cadmium-zinc alloy consists essentially of .alpha.-phase, .gamma.-phase and .epsilon.-phase silver-cadmium-zinc alloy crystallites, and the X-ray diffraction pattern of the .alpha.-phase silver-cadmium-zinc alloy crystallites does not exhibit line splitting.
38. A catalyst in accordance with claim 30 wherein the silver-cadmium-zinc alloy consists essentially of .alpha.-phase and .gamma.-phase silver-cadmium-zinc alloy crystallites, and the X-ray diffraction pattern of the a-phase silver cadmium-zinc alloy crystallites does not exhibit line splitting.
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US710,947 | 1976-08-02 | ||
| US05/710,947 US4096193A (en) | 1976-08-02 | 1976-08-02 | Production of alpha beta olefinically unsaturated alcohols |
| US71420176A | 1976-08-13 | 1976-08-13 | |
| US05/714,057 US4072727A (en) | 1976-08-13 | 1976-08-13 | Silver-cadmium-zinc alloy catalyst for hydrogenation of acrolein to allyl alcohol |
| US714,057 | 1976-08-13 | ||
| US714,201 | 1976-08-13 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1087597A true CA1087597A (en) | 1980-10-14 |
Family
ID=27418881
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA281,793A Expired CA1087597A (en) | 1976-08-02 | 1977-06-30 | Production of allylic alcohols |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS5318506A (en) |
| CA (1) | CA1087597A (en) |
| DE (1) | DE2734811A1 (en) |
| FR (1) | FR2360543A1 (en) |
| GB (2) | GB1549084A (en) |
| IT (1) | IT1086349B (en) |
| MX (1) | MX144402A (en) |
| NL (1) | NL7708266A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19819396C2 (en) * | 1998-04-30 | 2002-02-14 | Kataleuna Gmbh Catalysts | Catalyst for the selective hydrogenation of unsaturated alcohols, its production and use |
-
1977
- 1977-06-30 CA CA281,793A patent/CA1087597A/en not_active Expired
- 1977-07-26 JP JP8887177A patent/JPS5318506A/en active Pending
- 1977-07-26 NL NL7708266A patent/NL7708266A/en not_active Application Discontinuation
- 1977-07-28 FR FR7723281A patent/FR2360543A1/en not_active Withdrawn
- 1977-07-28 IT IT2629077A patent/IT1086349B/en active
- 1977-07-29 MX MX17003977A patent/MX144402A/en unknown
- 1977-08-01 GB GB3219677A patent/GB1549084A/en not_active Expired
- 1977-08-01 GB GB1543378A patent/GB1549085A/en not_active Expired
- 1977-08-02 DE DE19772734811 patent/DE2734811A1/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| IT1086349B (en) | 1985-05-28 |
| GB1549084A (en) | 1979-08-01 |
| GB1549085A (en) | 1979-08-01 |
| FR2360543A1 (en) | 1978-03-03 |
| NL7708266A (en) | 1978-02-06 |
| JPS5318506A (en) | 1978-02-20 |
| MX144402A (en) | 1981-10-08 |
| DE2734811A1 (en) | 1978-02-09 |
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