CA1051036A - Process for the production of butanediol - Google Patents

Abstract

APPLICATION FOR LETTERS PATENT

FOR

Abstract of the Disclosure A process for the production of butanediol which com-prises reacting propylene, oxygen and acid in the presence of a catalyst to produce a carboxylate which is reacted with hydrogen and carbon monoxide to produce diol esters which are de-esterified to butanediols.

Description

- l l ~ ' 8CH-1924 ~ ~ ~L~)S1~3~ 1 This invention relates to a process for the production of butanediol which comprises: (a) reacting propylene, oxy~e~
and a lower alkanoic acid in the presence of a catalyst comprisingl a Group VIII noble metal, or its salts or its oxides or mixtures l ~ I
s thereof at an elevated temperature to produce the corresponding - earboxylate; (b) reacting the carboxylate with carbon monoxide and hydrogen in the presence of a catalyst at an elevated tem-perature and pressure to produce diol esters; (c) de-esterifying the diol esters u'nder de-esterification conditions to produce ~ '`
lO ~ butanediols and an acid~ and (d) isolating the acid from the ¦
butanediols in a form suitable for use in (a).
~.
Back~round o the Invention ¦ Butanediol has been prepared by a number of diferent ¦methods~ U.S. Patent 3,060,244, for example, discloses prep æ ing ¦ ~' ~butane~diol by;reacting 1,3-butadiene with diborane in the presencel ' '' " ,,'!" 1l 0~ a saturated aLiphatic ether. U.~. Patent 2,686,817 describes ! :

the production of butanediol from tetrahydrofuran. Also. U.S. I '' ii 'Patents 2,9L2,471 and 2,928,884 disclose the preparation o ~1,4 ~ dichlorobu~ene to'which sodium hydroxide may be added to form I ' I ~ butenediol which in turn is hydrogenated to form butanediol.

British Patent 1,230,276 discloses a process for prèparing 1,4-;~1 butanedlol from if-butyrolactone. From'an article by White et al.

entitled "Catalytic Reductlon of Ozonides. I. Synthes`is of ~;lcohols from Olefins'' in 'ITetrahedro'n Le~ters"9 No. 39, `~ ~ ~ " , " ,, , ,' ' '~.,'' , '~
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~ OS ~ ~ 3 ; pp. 3587-3589, it is known ~hat a butanediol may be prepared from an olefin by reacting the olefin with ozone and an alcohoL to , ~ form an ozonide with a subsequent two-sta~e catal~tic hydro~ena- I ~ -tion to yield butanediol. U.S. Patents 2,300,598; ~,712,560;
` i 5 2,768,215; 2,9$3,604 and 3,294,849 disclose preparing 1,4 butyne~
diol from acetylene. Subsequent hy~rogenation of the 1,4 butyne- ¦ ~
diol yields the butanediol. ~owever, all of these methods involve¦ ;
. starting materials which are costly, or in ~he case of acetylene, involve a danger o explosions.

lD This invention relates to a no~el process for preparing butanediol from oxygen, propylene and a lower alkanoic acid, '. preferably acetic acid. The instant process proceeds by way of I several steps, i.~, preparing the carboxylate, hydroformylation, hydrogenation, de-esterification and recycling the acid. The ¦ ;
lS : ~ ¦general step of preparing the unsaturated e~ster by con~acting an olefin with a Group VIII catalyst in a reaction mcdium comprising !
a carboxylic acid is ilLustrated by U.S. Patents 3,190,912;
3,275,680 ;and 3,670,014 and South African Patent 701,077, for example. ¦

, The preparation of alcohols from olefins by the addition of carbon monoxide~and hydrogen to the olefin at elevated tempera~
ture and pressure in the presence of catalysts is disclosed in U.S. Pa~ents 2,670,365; 3,239,563; 3,420,898 and 3,496,203.

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, 1 ~escription of t1le Inv n~ion ,,s,,,, , It has been discovered that butanedio1 may be prcpared I ~.
~"~ ., from inexpensive starting materials as compared with the prior ,, ar~ methods, i.e., propylene, carbon monoxide, hydrogen and ¦l , 5 oxygen, and without the detonation bazards of acetyLene. Acetlc. lacid, in this process, merely acts as a mediati'ng agent and is not consumed in the overall reaction, 1~ :
, ~ Another objec~ of the instant invention Ls to provide a ~
,j~ l, novel process for preparing butanediol from inexpensive starting I ~, ~ lO materials, i.e., propylene, carbon monoxide, hydrogen and oxy~en :~,$~ ~ ~ by way o several intermediate steps~ ¦
'. I ~
, ~ ~. Preferably, the presen~ invention concerns a process for.the production of butanedlol which comprises: (aj reac.ting: `~:
propylene, oxygen and acetic acid in'the presence o a cata1yst 15 . comprising a Group VIII n~le metal, or its salts or its o~ides . or mix~ures ~here~f at an elevated temperature to yield allyl ~`' . acetate; (b) reacting the allyl acetate with carbon~monoxide and I ~
~,,"1 . hydro'gen:in the presence of a cat'alyst a~ an eLevated temperature 1 :
,," ~. , ,and pressure to produce the acetate e~sters.o ~he corresponding , 20 bu~anediols; (c) de-esterifying the mixture o.the,acetate esters ~
of the butanediols unde.r de-esterifioation conditio~s to produce ¦ :
,~ ~ the but,anediols and acetic acid; and (d) isolating ~he acetic~
.. . ~. acid from the butanediols in a form suitabLe for use in (a).
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105~1~3~
In he instant method, 911yl acetate i9 produced by reactin~ propylene, oxygen and a lower alkanoic acid, preferably l -¦ in the presence of a catalyst comprising a Group VIXI noble metal,~ ~ .
I or its salts~ or its oxides or mixtures ~hereof at an elevated S temperature.
.,,,,' . ,,:

i i This process may be illustrated, taking acetic àcid as an example, by the following equation:
' ' . " ' ..
CH2 ~ CH CH3 ~ CH3COOH ~ 1/2 2 ~~~~~ ~
; . . ., CH2 - CH-CH2-0-(;0-CH3 ~ H20 ~`;
wherein the yield average of allyl acetate is better than 96%.

.~, $ , . : ' The oxygen in the instant process may be used m pure elementary form, or in admixture with inert gases, for example, in the form of air. However~, it is preferred to work with con-centrated oxygen.
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. The propylene in the instant process may be used in lS pure eleméntary orm, or in admixture with inert gases, or ex ple, propane. I ~

,, . T~e acid~ which are employed in the instant inventionare lower alkanolc~acids having 1-6 carbon a~oms. Preferably ac~tic acid is employed herein.

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~ ¦ 8CH-1924 ~ 53~; :
Any type of acetic acid may be employed herein in the vapor phase. The acetic acid obtained from step (d) may be recycled to step (a) of the instant process.
. , .
Water may be used in the feed stream of the instant - ~ 5 invention. Preferably, wa~er in the gaseous phase is employed.
` The acetic acid obtained ~rom step (d) is aqueous and is suitable for use in step (a).

The reaction temperature or reaction pressure are not ~ critical. However, the preferred working temperature is in ~he ,~ 10 range of from about 100 to about 2~5C. while the preferred working pressure is in the range from atmospheric to about 150 psi. Somewhat higher or lower temperatures and pressures may, however, be used within the scope of the invention.
~i :~ ~ The catalysts which may be used in preparing the allyl aceta~e of ~this invention are the Group VIII noble metals, or~
, ~ . ~ .
their salts or their oxides or mix~ures thereof. Specific `
~ examples of these catalysts include~metals SUCh as palladium, ; l r~thenium, rhodium, pLatinum9 osmium, and iridium as well as`~ oxLdes and salts such as palladous propionate, palladous benzoate, ;
; , 20 palladous chloride 3 palladous bromide, palladous oxide, etc., ruthenium acetate, etc., rhodium acetate, etc., platinous benzoate, platinum dichloride, platinum oxideS etc., iridium chloride, etc., and the like and mixtures~thereo.
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Il 8CH-1924 11 ~0S:~L 1336 1 :
~¦ The preferred catalys~ system is a mixture of the ¦

Group VIII noble me~al and its salt~ A preferxed catalys~ is ; a mixture of palladium and palladous acetate.
'., '~' The catalyst is preferably applied to a support such as S aluminum oxide, carbon such as charcoal, silicas, and the like.

< ~ A promoter may be added to the catalyst which influences ac~ivity and selectivity. Among the preerred promoters are the transition metals, their salts, gold or copper.
.. , ' , The catalyst may be prepared in a number of di~ferent methods. For example, a support such as aluminum oxide is impregnated with a palladium ace~tyl acetonate solution in benzene and dried. The aluminum oxide is then impregnated wieh a solution¦
of potassium acetate in water and dried. The catalyst is then ¦
treated with propylenel The palladium is reduced to the ¦palladium metal. The catalyst thus obtained contains palladium I 1metal and potas-sium acetate in aboù~ lO parts ', I i ; Varying amounts of the catalyst can be used within the ,i ' . ! ` , `- ~
scope~of this invention. Amounts as low as about .1% based on weight of support have been found to be effective.
1 - .
2Q ~ 1n carrying out the process o~ this invention, a I ~ reactor tube is charged with the catalyst. A mixture of , ~, . . ~ ~ ' ~' ~ ` ' ' . ' " I . . I .
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8C~l-19~4 P ~ ~ 5 ~ ~ 3~
propylene, oxy~en and acetic acid is passed through the tube.
Upon leavin~ the reaction zone, the allyl aceta~e phase is ; separated from the aqueous phase and is fed into the second step of the overall process. Preferably, the propylene, oxy~en, and acetic acid are in the gasenus phase.
. . ..
It has been found that by proceeding by the method for preparing allyl acetate outlined above, the catalyst is not diminished in efectiveness even after 1000 hours of operation.
r; ~ . , Step (b) of the instant process for preparing butane-~ ~ 10 diol comprises reacting the allyl ace~ate with carbon monoxide i ~1 and hydrogen in the presence of a catalys~ at;an elevated tem-~: perature and pressure to produce the acetate esters of the corre- sponding butanediols.

Preferably, the reaction comprises reacting allyl ~i5 ~acetate with carbon monoxide and hydrogen in ~the presence of a , , catalyst at an elevated pressure and a temperature of from about 100 to about ~5dc. to produce the acetate esters of the corre- I
~i sponding ùutsnediols. I

. . : , I
The catalys~s which may be employed are the carbonyls ~ , 20 ~ of Group VIII noble metals, iron, cobalt, nickel, ruthenium, !':"`'' rhodium, palladiusn, osmium, iridium, platinum or mixtures thereof r' 1 . as well as the carbonyls mixed with these metals themselves may be used. A preferred cobalt catalyst comprises complexed cobalt.
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The complexed cobalt may be cobalt in complex com~ination with carbon monoxlde. A preerre~ cobalL catalyst in colnplex com~ina- ¦
¦tion with carbon monoxide is dicobalL octacarbonyl. ¦ ;
''' I I ., ¦ The active orm of the catalyst is a cobalt carbonyl ¦hydride which results ~rom cleavage.of the dicobalt octacarbonyl.

¦This cleavage ~akes place in situ under the hydrogen pressure . . , I
used in the reaction.

.,. ~, ~ . . ~ ~ .

; , ~ The cobalt catalyst can be recovered in three ~eneral forms: (1) as cobalt metal, (2) as cobaltous ion, or (3) as . , I
~ ` 10 ~ active catalyst. In the first two cases, the cobalt carbonyl in .,,,~ , .
~'''.. '7' ' : the reactor product is decomposed by heat andlor aqueous acids, Thermal decobalting to cobalt metsl can be accomplished by réleasing the carbon monoxide pressure from the hot liquid. How-`i ~ !ever, to facilitate the separation of the resulting solids ~rom ¦ ehe crude produc~, steam or hot water is often used. In that s~ ! manner, a cobalt-free organic phase can be decan~ed ~rom the aqueous slurry. Because or~anic acids are formed Ln the hydro-~ , formylation step as by-products, steam decobalting is a combina- I
i tion of thermal and acid decobalting. The resulting solids àre mixtures of cobalt~metal,-cobalt oxides, and cobalt salts. The ; use of aqueous acids for decobalting is usually carried out at ~elevated temperatures. This techn~ique requires good mixing to ;~ lensure con~act between the two liquid phases to transfer the l Icobalt from the orga~ic to the aqueous phase. Water-soluble ' I
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or~anic acids such as formic, acetic, or propionic may be used;
inorganic acids such as sulfuric or phosphoric are also efffec~ive.
The col~a1f~ salfs obtained from organic acid decobalting are some-. . tim~es recycled directly back f~O the oxo reactor. When inorganic acids are used, the salts are converted to the hydroxide or car- ¦
bonate for recycle or for conversion into the preferred form of cobalt.

. , The strongly acidic properties of cobalt hydrocarbonyl are taken advantage of in two methods used to recyc le active IO catalyst to the reactor. In one case, aqueous solutions o~
¦cobaltous lons are used to remove the cobalt carbonyl from the organic pha~e by formation of the cobalt salt, Cof~Co(C0)4)2. Thisl - $alt has a very high solubility in water and allows the recycle off ;~ concentrated catalyst, part of which is in the carbonyl form. In I 1 the second case, the organic liquid is decobalted with an aqueous ;
~, ¦alkali at hi8h pressures and temperatures to form the alkali-metal , Isalt of cobalt hydrocarbonyl. The volatile cobalt hydrocarbonyl I -¦ is re~enerated by contactin~ the aqu~ous solution with diluLe jmineral acid in the presence of a continuous flo~ o~ gas such as ! 1 20 nitrogen or synthesis gas. The hydrocarbonyl is ~hen transferred to the liquid ole~in feed by contacting in an absorption tower.
This process has found wide acceptance throughout the world. ¦
",, .
- The~reaction may be carried out at temperatures anfd pressures which are well known to those s~llled in ~he art.

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l! 8CH-1924 la3S~O;~ ~:

Preferably, presswres of from about 1500 to about 5000 psi are emPloyed. T~mpera~ures in the ran~e of from about 1~0 to about l2500c. and preEerably from about 150 to about 2100C. are employed.
Somewhat higher or lower temperature and pressures may, however, I
1 be employed within the scope of this inve~ ion.

. 1 :
;~ There are a number of ways in which step ~b) may be carried out. Among these processes are those in which the reac~
tion is started at rela~ively low tempera~ures, i.e., 125-150C. j and is completed at elevated temperature of 180C. or greater.
~I0 ~Al~ernàtively the whole process may be carried out at the higher temperature.
~ .
It has been s~rprisingly discovered that the following compounds were in evidence following completion of this reacton:

H0CH2cH2cH2cll20Ac ~OH(CH2)4H ~ AcO(CH2)4OAc 15; ¦¦-4-acetoxybutanol1,4-butanediol 1,4-butanediol~
diacetate HO-CH2CHCH20Ac ~HOCH2CHCH20H + AcOCH2CHCH20Ac CH3 CH3 CH3 l ¦ 2-methyl-3-ace~oxy-2-methyl-1,3- 2-rnethyl-1,3-propane- ¦ -propanol propanediol ~ diol diacetate , ', ~`, . ' ~ ' ,, ' , ~ ' . ''. ' :~i .
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~ ~ ~ 8CH-19~4 , ~
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OAc OH OAc ~HOCH2CHCH2c~13 ~ HOCH2CHCH2CH3 -~ ACOCH2CHCH2CH3 ¦ 2-acetoxybu~anol 1,2 butanediol 1,2-butanediol , I I diacetate ,~,;",, ~ . ' . I ~
! Thus, in actuality, nine compounds were found: 4-¦ acetoxybutanol and its two disproportionation products; 2-methyl~
3-acetoxypropanol and its two disproportionation products; and

2-acetoxybutanol and its two disproportionation products.

` ¦ :
.~ This reaction may be carried o~ in the presence of a :~ catalyst which is modified. This catalyst is~modiied by the inclusion of phosphorus-containing or arsenic~-containing ligands j in the molecule. Preerably alkyl, aryl, and heterocyclic phos-'i `q Iphines are employed. Preferred phosphines are trisubstituted phosphines. Most preferred are the trialkyl s~bstituted phos-phines such as tri-n-butyl phosphine. ;These catalysts are ! :
; 15 ¦l~prepared in accordance with the methods descrlbed in U.S. Patents I
¦3,239,56g; 3,4~0,898 and 3,496,203, for example.

When using the modified catalyst, ca~alyst recycle can be ecfected by directly using ~he distillation ends which contain I ~`
~` the phosphine~-modified cobalt carbonyl in active form.
;,':1 ` , ¦ Use of these phosphine-modified catalysts allows the ; process to be~operated at lower pressures than when using the . I

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Si~
unmodified dicobalt carbonyl catalyst. Pressures in the range of from about 400 to about 1000 psi may be used.
,' 1 11 ' ~; ¦ IL has been discovered that when the modified catalyst is used, only ~he 4-acetoxybutanol and 2-acetoxybutanol systems are in evidence. .

The reaction may be carried out in the presence of a . solvent. Any solvent which is inert or does not interfere with the reaction under the conditions employed may be used. Pre-ferred solvents are inert organic solven~s? partlcularly aromatic I
~10~ ¦or aliphatic hydrocarbons.

" The rat~ios of hydrogen to carbon monoxide of the ynthesis ~as ~carbon monoxide and hydrogen) charged may vary widely within~the scope of this invention. Suitable ratios`of hydrogen Lo carbon monoxide comprise those within the ratio of ,ifrom~about 1:3 to about 10:1. Preferred ratios of hydro~en to I' Icarbon monoxide are from about 1:1 to about 2:1. ~ er or ~, lower ratios, however, are within the 5cope of thls invention.
. , Step ~d) of the overall process comprises de-esterlfying' ~the mixture of the acetate esters of the butanedlols under de-j` 20 ¦esterification.conditions to produce the butanediols~and acetic ~i` acid. The de-esteriflcation takes~place -by any of the well known ~ methods in the art as by hydrolysis or`alcoholysis, for exarllple.

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~ ¦1 8CH-1924 Hydrolysis a"d alcoholysis may Lake place in the presence o~ a ¦ catalyst sucll as an acid, base, or acidlc or basic non-exchan~e ¦ resin, for example, A preferred method ~or de-esterifyin~ the ¦ mixture of the acetate esters of the bu~anediols to butanediols is by hydrolyæing these acetate es~ers in the presence of water and alkali. B~tanediols and the corresponding acetates are ¦ produced, The butanediols may be isolated from the salts by , ~1 ! extraction with isobutanol, for example. Preferred alkali are the : I I . ., ~¦ I alkali metal and alkaline earth metal hydroxides. The alkali ` lO ~ ~1 ace~ate so produced is acidified to produce the acetic acid. The ~
, preferred acidifyin~ ager.~s are the inor~anic acids, Many methods!
or isolatin~ the acetic acid are well known,such as distillàtion, ¦ ~or example, The ace~ic acid so produced is in a form suitable ¦¦ for use as a startin~ material in the preparation of allyl acetate!.

~15 tl As stated, the pre~erred method of de-esterifyin~ the mixture of the acetate esters of bu~anediols is by hydrolysis in the presence of water and alkali. The bu~anediols produced com-¦i pris:e in admixture the followin~ compounds:
.,.~ ,.
'~ . ' ' . i O(CH2)40H 1,4-butanediol ¦20 I about 7 parts ~':' j ;, : I

O~H2CHCH2OH 2-mechyL-1,3-propanediol about l.5 parts '': I

~; 1` -13~ ' I
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!i , ¦~ 8CH-1924 1,2-butanediol about 1.5 par~s When the mix~ure of the acetate esters of the butane-~ Idiols produced using the modified cobal~ carbonyl catalyst are ; ~ 5 ¦I de-esterified by hydrolysis in the presence of w~ter and alkali?
the butanediols produced comprise in admixture the following ~ Icompounds: .
',:i"'", I . 1 ,., ` ¦ HO(CH2)40H 1,4-butanediol about 3 parts HOCH2CHCH2CH3 1,2-butanediol about 2 parts '.''~, ' , . ~ ' . ' '' ' ' , ~ , The desired product 1,4-butanediol can be separated from ` the isomeric by-products in ~reater than 99% purity by distilla-,, ~ li , tion.
11 ' The overall process for preparing butanediol as des~
:: cribed may be carried out semi-continuous ly.
' l A preferred process for the production of butanediol ~~
comprises: (a) reacting propylene, oxy~en and ace~ic acid over I -a solid catalyst comprising a palladium metal, its salt and ., . . ' ~ ' , ~ . -14- ~ ~
,. , , , . . .
. ~ , ~ ~ 1 ' ~C~-1924 ~ .
1 ~5i~
I
imixtures thereof at a temperature of from about 100 to about 225C. and a pressure of from atmospheric to about lS0 psi to jproduce allyl acetate; (b) reacting the allyl acetate with ¦carbon monoxide and hydrogen in ~he presence of a catalyst con-¦sisting essentially of cobalt in complex combination with carbon : ¦monoxide at a pressure of from about.2000 to about 4000 psi at a ,¦temperature of from abou 150 to about 210C. to produce a mixture ¦comprising ~he acetate esters of the corresponding butanediols;
¦I(c) de-esterifying the mixture of the acetate esters of the butane-; 10 Idiols so produced in the presence of water and an alkali metal hydroxide or an alkaline earth me~al hydroxide to yie ld butane- ¦
: Idiols and the corresponding alkali metal aceta~e or alkaline j learth metal acetate; (d) acidifying the acetate so produced with , ,an inorganic acid to produce acetic acid which is.isolated ln a Iform suitable for use in (a) .

Another preferred process for the production of butane-` !Idiol comprises: (a) reacting propylenie, oxygen and acetic acid I~in the presence of a catalyst comprising a palladium meta]., its . .. salt and mixtures` thereof at a temperature of from aboat~ 100 to ' 20 ¦abou~ 225 C. and a pre.ssure of from atmospheric to about 150 psi , . Ito produce allyl acetate; ~b) reacting the allyl acetate wlth ;~
j Icarbon .monoxide and hydrogen in the presence of a catalyst con- :
~ . ~sisting essentially of cobalt in complex combination with carbon .~ 'monoxide and a trialkyl substituted phosphine at a pressure of from :~ 25 labout 400 to about IOQ0 psi at a temperature of from about 15~

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l 8CH-1924 .. lOS~

to about 210~C. to produce a nlix~ure comprisin~ the acetate esters¦
oL t~l~ corresl)olldin~ butan~cliols; (c) de-est~ri~yin~ the mix~ure ¦lof the acetaLe esters of the butanedioLs so produced with water ¦ and an alkali metal hydroxide or an alkaline ear~h me~al hydroxide to yield butanediols and the corresponding àlkali metal acetate ; or alkaline earth metal acetate; (d) acidifying tlle acetate so produced with an inorganic acid to produce acetic acid which is isolated in a form suitable for use in (a~. ¦
'.,! , ¦ . I : .

,; ¦ Uescriptiotl of ti-e Preferred Embodiment ;.~. . I
The following examples are set forth to illustrate more t~ ~, , clearly the principle and practice of this invention to those skilled in the art. Unless othen~ise specified, where parts or percents are mentioned, they are parts or percents by wei~ht.

Example 1 . ~ . i }~ ~ 15 ~ ~ ~ ~ A miniplant is constructed and operated ~or the produc- ' ~
. ` , ,~
I tion of bu~anediol from propylene via the disclosed cyclic process.

i An ~ ft. x 1 in. diameter stainless steel tube is charged with ~I j one liter (l~00 grams) of catalyst composed of alumina impregna~ed;

I ~ ~ wlth 0.3/O palladium and 3% potassium acetate. The reactor tem-perature is maintained at 180~ (circulating oil jacket) while a ;;'l mixture per hour of 2000 grams of propylene, 600 ~rams of acetic ~ acid, 170 grams of oxygen and 900 grams of water, all in the I

.~ ~aseous phase, lS passed through. The output per hour is a " ~,~ ,.. . . .. .. . ..

8CH-19~ 1 ~5 ~ 3~
mixture of about 960 grams of allyl acetate and 1050 ~rams of water, in ad~ition to 18 ~rams ~ (();2 and the excess propylene and oxy~en, wllich are recycled. The allyl acetate phase, which contains about 0.1~/0 acetic acid, is separated and used directLy ¦in the second sta~e of the process.
I . I
A two liter stirred autoclave heated at 125~ is ¦pressurized with 3000 psi of 2:1 hydrogen/caxbon monoxide and charged with a mixture of 400 grams o allyl acetate, 16 grams ` ¦of dicobalt octacarbonyl and 400 ml, of benzene. An exothermic reaction and ~as uptake ens~es. The exotherm and external heating increase the temperature to 180C. After 3~ minutes at that temperatureJ the mixture Ls`pumped from the autoclave, cooled ¦¦and vented.

~ The product solution is decobalted by exposure to ~àir f,~;~ I5 ~ at 80C for 15 minutes. (The cobaltous acetate which precipitates -I'is~filtered off and transformed to active dicobalt octacarbonyl t - i ~ ~ ! by subjection to hydrogen/carbon monoxide at elevated temperature ,~ and pressure [160C, 3000 psi]). The combined e~fluent from five ,~ ~ .such oxo conversions is di5tilled and the solvent recovered. VPC

examination of the residue indicates the presence of 4~acetoxy-, ~ ¦butanol, 3-acetoxy-2~methylpropanol, 2-acetoxybutanol, and their , ." i .
respective diol and diacetate disproportionation products. The ~, ~mixture is hydrolyzed with 5 li~ers of 5N ~aOH. After one hour at reflux (110C) the mixture is cooled and neutralized t to pH 10) , .
I
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I 8CH~1924 . I l~Si(~
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with H2S04, then ex~racted with isobutanol. Distillation of the extract a~fords 1682 grams of mixed diols (93~. yield), b.p. 7U-90 1 mm. VPC analysis indicates the presence of 1,4~butanediol, 2-¦methyl-1,3~propanediol and 1,2-butanediol in 7 : 1.5 : 1.5 ratio.
¦ (These diols are separable by distillation.~ I

i I II The aqueous phase and distillation residue are combined 1l 1 ¦¦and acidified to pH 3. Distillation affords the acetic acid (95%
recovery) in a form suitable for use (about 40%) in the propylene 0 allyl acetate conversion.
' 1 . j ¦ The process as described is operated semi-continuously ¦ to provide butanediol at about two pounds per ho~r.
~r~''.' .
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! A mixture of 100 g. of allyl acetate (obtained as in ',.,~
Example 1), 6 0 grams of cobaltous acetate tetrahydrate and 200 ` l :15 1I ml. of hexane is subjected to 3000 psi of 2~ ydrogen/carbon Ijmonoxide in a one liter stirred autoclave and heated to 170C, at ¦which point an exothermic reaction and gas uptake begin. The ¦mixture is kept at l80-19~C for one hour, then cooled. A two- ', Iphase liquid is produced. Removal o the solvent and decobalting !
,~'; 20 ¦leaves a monoacetate mi~ture similar in composition to ~hat des-ribed in Example 1.

' - 1l 8~H~1924 ¦ ~Iydrolysis with 300 ml. oE 5 N NaOH, extraction an~

~¦distilLation as in Example 1 affords 76.5 grams (85~/o yield~ of the mixed diols 1,4-butanediol, 2-methyl-1,3 propanediol and 1,2-butanediol, in 7.~ : 1.5 : 1.3 ratio~
s ~
Example 3.

' ¦¦ A mixture of 100 grams of allyl acetate, 4.0 grams of:
- dicobalt octacarbonyl, 4.8 grams of tri-n-butylphosphine and 200 .,- ~ .
ml. of benzene is sub jeeted ~o 300 psi of carbon monoxide and 600 psi of hy~ro~en and hea~d at 180-18g~ for one hour. Gas is replenished ~2:1 H2/CO) to maintain the pressure at 900-1200 psi.
~ ' , I ~, The products are distilled, affordin~ an acetate mixture ¦
that is somewhat less complex than in the case of Example 1. (The distillation residue contains the intact catalyst, which is directly recycleable.) Hydrolysis, extraction and distillation ¦
lS ~¦las in the above Examples affords 54.9 grams (61% yield) of mixed diols, 1~4-butanediol and 1,2-butanediol in 3:2 ratio. The 2-methyl-113-propanediol is produced in less than 1% yield wit~ this I
~procedure. I ~ ' :"`.1 : . . .
..
;Example 4 1 ~
i . I : .'.

A mixture of 100 grams of allyl acetate, 5.0 grams of I ~
cobaltous acetate tetrahydrate~ 10.0 grams of tri-n-bLttylphosphine I : ' ; and 200 ml. of benzen¦e is subjected to 2400 psi of 2:1 hydrogen/

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. I .
,' ,~ .

I ~CH 1924 t ~ S~
¦carbon monoxi~e~ The solution is heated at 180~ 5~ f~r one hour I
¦then cooled and distilled as in ~xaIll~31e ~. Hydrolysis, extractioIl, ¦¦and distillation of the aceta~e mixture as above affords 49.4 grams of diols (55% yield) ~ 1,4-butanediol and 1,2-butanediol in 2 :1 ratio .
. I . I
¦¦ It should, of course, be apparent to those skilled in the art that changes may be made in the particul~r embodiments ¦ of the invention described which are within the full intended scope of the invencion as deLined by ~he appended claims.

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Claims (33)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A process for the production of butanediol which comprises:
(a) reacting propylene, oxygen, and a lower alkanoic acid in the presence of a catalyst comprising a Group VIII noble metal, or its salts, or its oxides or mixtures thereof at an elevated temperature to produce the corresponding carboxylates;
(b) reacting the carboxylates with carbon monoxide and hydrogen in the presence of a hydroformylation-hydrogenation catalyst at an elevated temperature and pressure to produce diol esters;
(c) de-esterifying the diol esters under de-esterifica-tion conditions to produce the butanediols and a carboxylic acid;
(d) isolating the acid from the butanediols in a form suitable for use in (a).

2. A process for the production of butanediol which comprises:
(a) reacting propylene, oxygen and acetic acid in the presence of a catalyst comprising a Group VIII noble metal, or its salts, or its oxides or mixtures thereof at an elevated tem-perature to produce allyl acetate;
(b) reacting the allyl acetate with carbon monoxide and hydrogen in the presence of a hydroformylation-hydrogenation catalyst at an elevated temperature and pressure to produce the acetate esters of butanediols;

(c) de-esterifying the mixture of the acetate esters of the butanediols so produced under de-esterification conditions to produce the corresponding butanediols;
(d) isolating the acetic acid from the butanediols in a form suitable for use in (a).

3. The process of claim 2 wherein the Group VIII noble metal salts are selected from the group consisting of the Group VIII noble metal acetates, benzoates, propionates, halides and mixtures thereof.

4. The process of claim 2 wherein the catalyst in (a) is a mixture of a Group VIII noble metal and its salt.

5. The process of claim 4 wherein the mixture of the Group VIII noble metal and its salt is a mixture of palladium and palladous acetate.

6. The process of claim 2 wherein the catalyst support in (a) is selected from the group consisting of aluminum oxide, silica and carbon.

7. The process of claim 2 wherein (a) is carried out at a pressure of from atmospheric to about 150 psi.

8. The process of claim 2 wherein (a) is carried out at a temperature of from about 100 to about 225°C.

9. The process of claim 2 wherein the propylene, oxygen and acetic acid are reacted in the presence of water.

10. The process of claim 2 wherein the propylene, oxygen and acetic acid are reacted in the gaseous state.

11. The process of claim 2 wherein the catalyst in (b) comprises complexed cobalt.

12. The process of claim 11 wherein the complexed cobalt catalyst comprises cobalt in complex combination with carbon monoxide.

13. The process of claim 12 wherein the cobalt in complex combination with carbon monoxide is dicobalt octacarbonyl.

14. The process of claim 2 wherein the catalyst in (b) comprises cobalt in complex combination with carbon monoxide and a trisubstituted phosphine.

15. The process of claim 14 wherein the trisubstituted phosphine is a trialkyl substituted phosphine.

16. The process of claim 15 wherein the trialkyl sub-stituted phosphine is tri-n-butyl phosphine.

17. The process of claim 2 wherein (b) is carried out at a temperature of from about 150 to about 210°C.

18. The process of claim 2 wherein (b) is carried out at a pressure of from about 2000 to about 4000 psi.

19. The process of claim 2 wherein (b) is carried out at a pressure of from about 400 to about 1000 psi.

20. The process of claim 2 wherein (b) is carried out in an inert organic solvent.

21. The process of claim 20 wherein the inert organic solvent is an aromatic or aliphatic hydrocarbon.

22. The process of claim 2 wherein the butanediol acetates comprise in admixture 4-acetoxybutanol and its dispro-portionation products which are 1,4-butanediol and 1,4-butanediol diacetate, 2-methyl-3-acetoxypropanol and its disproportionation products which are 2-methyl-1,3-propanediol and 2-methyl-1,3-propanediol diacetate, 2-acetoxybutanol and its disproportionation products which are 1,2-butanediol and 1,2-butanediol acetate.

23. The process of claim 2 wherein the mixture of the acetate esters of the butanediols are de-esterified by hydrolyzing in the presence of water and alkali to produce the butanediols and alkali acetate.

24. The process of claim 23 wherein the alkali is selected from the group consisting of alkali metal and alkaline earth metal hydroxides.

25. The process of claim 2 wherein the alkali acetate is acidified with an inorganic acid to produce acetic acid which is isolated in a form suitable for use in step (a).

26. The process of claim 2 wherein the butanediol com-prises in admixture 1,4-butanediol, 2-methyl-1,3-propanediol and 1,2-butanediol.

27. A process for the production of butanediol which comprises:
(a) reacting propylene, oxygen and acetic acid over a solid catalyst comprising a palladium metal, its salt and mixtures thereof at a temperature of from about 100 to about 225°C. and a pressure of from atmospheric to about 150 psi to produce allyl acetate;
(b) reacting the allyl acetate with carbon monoxide and hydrogen in the presence of a catalyst consisting essentially of cobalt in complex combination with carbon monoxide at a pressure of from about 2000 to about 4000 psi at a temperature of from about 150 to about 210°C. to produce a mixture comprising the acetate esters of the corresponding butanediols;
(c) de-esterifying the mixture of the acetate esters of the butanediols so produced in the presence of water and an alkali metal hydroxide or an alkaline earth metal hydroxide to yield butanediols and the corresponding alkali metal acetate or alkaline earth metal acetate;
(d) acidifying the acetate so produced with an inorganic acid to produce acetic acid which is isolated in a form suitable for use in (a).

28. The process of claim 27 wherein the catalyst in (a) is a mixture of palladium and palladous acetate.

29. The process of claim 27 wherein the catalyst con-sisting essentially of cobalt in complex combination with carbon monoxide in (b) is dicobalt octacarbonyl.

30. A process for the production of butanediol which comprises:
(a) reacting propylene, oxygen and acetic acid in the presence of a catalyst comprising a palladium metal, its salt and mixtures thereof at a temperature of from about 100 to about 225°C.

and a pressure of from atmospheric to about 150 psi to produce allyl acetate;
(b) reacting the allyl acetate with carbon monoxide and hydrogen in the presence of a catalyst consisting essentially of cobalt in complex combination with carbon monoxide and a trialkyl substituted phosphine at a pressure of from about 400 to about 1000 psi at a temperature of from about 150 to about 210°C. to produce a mixture comprising the acetate esters of the corre-sponding butanediols;
(c) de-esterifying the mixture of the acetate esters of the butanediols so produced with water and an alkali metal hydroxide or an alkaline earth metal hydroxide to yield butane-diols and the corresponding alkali metal acetate or alkaline earth metal acetate;
(d) acidifying the acetate so produced with an inorganic acid to produce acetic acid which is isolated in a form suitable for use in (a).

31. The process of claim 30 wherein the catalyst in (a) is a mixture of palladium and palladous acetate.

32. The process of claim 30 wherein the trialkyl sub-stituted phosphine in (b) is tri n-butyl phosphine.

33. The process of claim 30 wherein the catalyst con-sisting essentially of cobalt in complex combination with carbon monoxide in (b) is dicobalt octacarbonyl.