CA2124189A1 - Manufacture of trimethylolpropane - Google Patents
Manufacture of trimethylolpropaneInfo
- Publication number
- CA2124189A1 CA2124189A1 CA 2124189 CA2124189A CA2124189A1 CA 2124189 A1 CA2124189 A1 CA 2124189A1 CA 2124189 CA2124189 CA 2124189 CA 2124189 A CA2124189 A CA 2124189A CA 2124189 A1 CA2124189 A1 CA 2124189A1
- Authority
- CA
- Canada
- Prior art keywords
- formaldehyde
- alcohol
- hydrogenation
- trimethylolpropane
- butyraldehyde
- 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.)
- Abandoned
Links
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
- C07C29/14—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
-
- 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
- C07C29/36—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring increasing the number of carbon atoms by reactions with formation of hydroxy groups, which may occur via intermediates being derivatives of hydroxy, e.g. O-metal
- C07C29/38—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring increasing the number of carbon atoms by reactions with formation of hydroxy groups, which may occur via intermediates being derivatives of hydroxy, e.g. O-metal by reaction with aldehydes or ketones
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Trimethylolpropane of high purity is efficiently made by mixing the aldol reaction product of formaldehyde and n-butyraldehyde with at least about 20 wt % of a lower alcohol prior to hydrogenation to allow recovery of high purity product by simple distillation. In a less preferred mode, the alcohol may be added after hydrogenation, resulting in a smaller improvement over previous processes.
Description
`YO94/07831 ~ 3 ~ PCT/US93/08140 MANUFACTURE OF TRIMETHYLOLPROPANE
Technical Field This invention relates to the production of trimethylolpropane and particularly to conducting the hydrogenation of the reaction product of n-butyraldehyde ( NBAL) and formaldehyde in the presence of at least 20% of a lower alcohol of the formula RlR2CHOH where R1 and R2 are independently hydrogen or alkyl groups having 1 to about 5 carbon -atoms but together have no more than 6 carbon atoms.
Background of the Invention The conventional production of trimethylolpropane typically entails the reaction of n-butyraldehyde and formaldehyde ~usually an aqueous solution~ to obtain the aldol reaction product which may then be hydrogenated over a hydrogenation catalyst either with or without treatment intended to purify it. Representative of the prior art are U.S~ Patents 4,122,290 and 4,514,578 to Immel et al and 4,594,461 to Merger et al, which may use a trialkyl-amine catalyst in the aldol step. While the conventional commercial processes have served more or less satisfactorily in the context of the state of the art, our process is much more efficient and the product is much more pure.
Commercially, formaldehyde is available in either of two forms, paraformaldehyde or as an WO94/07831 PCT/US93/0814~-2 l ~ 8 3 aqueous solution ~referred to herein as aqueous formaldehyde). Paraformaldehyde is a crystalline solid consisting of a linear polymeric form of formaldehyde of the molecular formula, HO(CH2)nH
where n - 8-100. Aqueous formaldehyde consists predominently as formaldehyde in its monomeric form.
On standing, it will gradually react with itself forming oligomeric formaldehyde and paraformaldehyde. This is commonly inhibited by sdding up to 15% methanol as a stabilizer. Where "formaldehyde" is used hereafter, we mean that either formaldehyde in the form of paraformaldehyde or aqueous formaldehyde is acceptable unless otherwise specified.
K}ein, in U.S. Patent 3,076,854, treats a crude trimethylolpropane by solvent extracting with an alcohol such as amyl alcohol, re-extracting with water, heating with methanol in the presence of a strong acid, and passinq through an ion exchange bed to remove metals. Purification was not accomplished by distillation as in the present invention.
In East German Patent 142,184, Dietze et al follow a more or less conventional TMP
preparation by distillation to obtain a distillation bottoms comprising about 3% of the reaction product;
this bottoms portion is treated with methanol and passed through a strong acid resin to liberate additional TMP.
Merger et al, in European Patent 289,921, treat the hydroqenated effluent of the trialkylamine catalyzed reaction of n-butyraldehyde and aqueous formaldehyde in one of two ways. In the first they ~094/07831 ~ PCT/US93/08140 remove water and excess trialkylamine by distillation at 100-200C. Trialkylamine which is tied up as its formate salt reacts with trimethylolalkane under distillation conditions to give free trialkylamine and formate esters of the polyol. They then add methanol and either an alcoholate of an alkalai or alkaline earth metal to liberate the trimethylolalkane which is recovered by distillation. The second method involves removal of ~-the excess water and free trialkylamine by distillation followed by the addition of methanol to the distillation bottoms. This mixture is then heated to 100-200C under pressure, and trialkylamine and methylformate are removed by distillation. The water concentration in ~his instance is quite stringent and can be no more than 5-15%. While the product is finally recovered by distillation, no mention is made of purity.
Our process does not require any special treatment before alcohol addition and leads to a product of very high purity.
Raue et al, in Example 1 of East German Patent 273,434, describe a process for recovering formaldehyde from the Ca(OH)2 catalyzed reaction of higher aldehydes with formaldehyde to form polymethylolalkanes. The treatment first requires neutralization of the reaction effluent followed by addition of methanol, stripping of lights at 50C
under vacuum, treating with acetonitrile, removing calcium salts, addinq additional methanol and stripping up to 90C to remove lights includinq g formaldehyde. No mention is made of product recovery. Our process is simple, different, and leads to high purity TMP.
Summary of the Invention Our process involves an aldol reaction of n-butyraldehyde and formaldehyde followed directly by a hydrogenation step conducted in the presence of at least about 20% by weight lower alcohol of the formula RlR2CHOH where Rl and R2 are independently hydrogen or alkyl groups having l to about 5 carbon atoms but together have no more than 6 carbon atoms.
In the hydrogenation step the catalyst, preferably copper chromite, is used at temperatures in the range of about 100C to about 200C, and relatively low pressures, in the range of 500 to about 3000 psi. Our invention will give good yields of desired product, having very high purity, as will become apparent in the section below.
To make the hydrogenation feed, the n-butyraldehyde and the formaldehyde should be employed in molar ratios of about 0.5 to about l0, preferably 0.5 to 5 and most preferably about l to about 2.5.
We prefer to use a hydrogenation feed containing 20 to 90% alcohol, preferably 30-60%
alcohol, and most preferably 50% alcohol; the preferred alcohol is methanol. The alcohol may be added after hydrogenation; however, the most benefit is derived from adding the alcohol prior to hydrogenation, which is our preferred mode.
`~094/07831 2 1 2 ~ 3 PCT/US93/08140 Detailed Description of the Invention Our invention will be described with particular attention to the examples below.
SPecific Procedure usinq Paraformaldehvde I ;
A specific reaction using paraformaldehyde ~
may be described as follows: The reaction is -performed in a reflux apparatus wherein l.00 equivalent of NBAL, 2.50 equivalents of -paraformaldehyde, and about 0.04 to 0.05 equivalents of triethylamine have been placed under an inert atmosphere. With overhead stirrin~, the reaction mixture is heated, initially, in a water bath at 50C; the temperature is gradually increased to 80~C
over a one-hour period. The reaction is continued for an additional hour and terminated. The clear molten liquid is diluted in an alcohol, preferably methanol, and hydrogenated by passing the reaction solution over a conventional copper chromite catalyst at about 160C and about l000 psi ~2 High purity TMP product (>99%) is recovered in good yield by distillation.
Specific ~rocedure usinq Aqueous Formaldehyde Another specific reaction using agueous formaldehyde may be described as follows: The reaction is performed in a reflux apparatus wherein l.00 equivalent of NBAL, 2.50 equivalents of aqueous formaldehyde, and about 0.04 to 0.08 equivalents of triethylamine have been placed under an inert atmosphere. Preferably the NBAL is added dropwise WO94/07831 PCT/US93/08~4 3~ ~?~ a over a 0.25-1 hour period to the stirred mixture of aqueous formaldehyde and triethylamine. With overhead stirring, the reaction mixture is heated in a water bath at 60C for two hours. The clear liquid is diluted in an alcohol preferably methanol and hydroqenated by passing the reaction solution over a conventional copper chromite catalyst at about 160C and about 1000 psi. High purity TMP product (>99%) is recovered in good yield by distillation.
General Procedure usinq Formaldeh~de More generally, with 1 equivalent of NBAL
we may place in a reaction vessel from about 2 to about 10 equiv~alents of formaldehyde and about 0.001 to about 1.0 (preferably about 0.05 to about 0.5) equivalent of a tertiary amine catalyst. The reaction mixture is stirred at 60-80C until most of the NBAL is consumed. The resulting solution is diluted in an alcohol preferably methanol and hydrogenated using a hydrogenatinn catalyst. High purity TMP product is obtained in good yield by distillation.
Example 1 ~ series of batch aldol reactions were performed in glassware as follows:
A. n-Butyraldehyde (1069.3 g, 14.89 mol), paraformaldehyde (1223.4 g, 37.07 mol), water (132.4 g, 7.35 mol)~ and triethylamine t75.0 g, 0.74 mol) were added into a 3-neck roundbottom flask -W O 94/07831 2 1 .~ PC~r/US93/08140 equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was placed in a water bath at 50C. The bath was heated to a temperature of 80C over a period of 2 hours at which point >99% of the n-butyraldehyde was reacted.
The reaction mixture was diluted in methanol to make a 50 wt % aldol in methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of copper chromite at 160C, 0.5 hr 1 liquid hour space velocity (LHSV), and 1000 psig H2. The resultant hydrogenation product was batch, distilled ~' using an 8-inch long packed column to recover high puritr trimethylolpropane product (99.18% purity, ' 73.3% recovery).
B. n-Butyraldehyde (643.7 g, 8.93 mol), aqueous formaldehyde (1811.2 9, 22.32 mol), and triethylamine ~45.2 5, 0.45 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 40C. The bath was heated to a temperature of 60C over a period of 1 hour and continued for an additional hour at which point 97% of the n-butyraldehyde was reacted. The reaction mixture was diluted in methanol to make a 50 wt % aldol in methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr LHSV, and 1000 psig H2.
The`resultant hydrogenation product was batch WO94/07831 PCT/US93/0814r ~ :1 2 ~ 3 ~ ' :
distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.07% purity, 68.4% recovery).
C. Example l.A. was repeated except that the aldol reaction mixture was diluted in n-butyl alcohol rather than methanol to make a 50 wt % aldol in n-butyl alcohol solution. High purity trimethylolpropane product was obtained (99.15%
purity, 72.3% recovery).
D. The "controlN experiment was performed by repeating Example l.B. without adding the methanol solvent prior to hydrogenation. The trimethylolpropane produst recovered was of lower purity~(98.33% purity, 73.0% recovery).
The data for these four experiments are summarized in Table I. The results reveal the surprising improvement in trimethylolpropane purity made possible by the addition of a suitable alcohol solvent to aldol reaction product prior to hydroqenation.
~vo 94/07831 '~ ,'?~ PCT/US93/08140 Table I :~
Exa~ple lA. lB. ~C. lD.(Ucontrol~) HC~ paraform- aqueous paraform- aqueous 5ype aldehyde formaldehyde aldehyde formaldehyde ~dded n-butyl 5Olvent ~Pt~nol ~t~an51 ~leobo~ none So~ve~t Le~el 0 ~ 50 ~ 50 % S S
~ cor~t~lnod) Di~tilled ~us~ty %) 99.18 ~ 9~.0~ ~ 99~5 ~ 98.3 ~ecovery 73 4 ~ ~ 7~ ~ 7~ g WO9~/07831 PCT/US93/0814~
~ ~ 2 ïl~9 ExamPle 2 Two batch aldol reactions were performed in glassware as follows:
A. n-Butyraldehyde (772.4 g, 10.71 mol), aqueous formaldehyde (2173.4 g, 26.78 mol)~ and triethylamine (54.2 g, 0.54 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 40C. The bath was heated to a temperature of 60C over a period of 2 hours at which point >99%
of the n-butyraldehyde was reacted. The reaction mixture was diluted in methanol to make a 9~ wt methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr 1 LHSv, and 1000 psig H2.
The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.02~ purity, 66% recovery).
B. n-Butyraldehyde (943.4 g, 13.08 mol), paraformaldehyde (1079.3 g, 33.71 mol), water (116.8 g, 6.48 mol) and triethylamine (66.2 g, 0.65 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 50~C. The bath was heated to a temperature of 80C over a period of 1 hour and continued for an additional hour at which point 99% of the n-butyraldehyde was reacted. The reaction mixture was diluted in methanol to make a ~':
:
'~/094/07831 ~,~ 2 ;1 i ~ ~ PCT/US93/08140 20 wt % methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr l LHSV, and lO00 psig H2. The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.01% purity, 91%
recovery).
The data for these two experiments, when ::: compared to Example lA. and Example lB., show similar TMP distilled purities (>99%) in good '`
recoveries using higher (90 wt %) and lower (20 wt %) methanol levels. These results are displayed in Table II.
~.
W O 94/07831 PCT/US93/0814~-S~bl- ~I
Ex~plelA. 1~. 2A. 2EI.
HCHOparaform- aqu~ous equ~ou~ paraform-Type aldehyde roraaldebyde formalde~yde aldehyde Added ~olvent ~ethanol ~et~anol ~ethanol ~et~anol .
Solvent Level (wt %) 50 % 50 % 90 % 20 %
.
Distilled TMP
Purity (wt %) 99.~8 ~ 99.0~ % 99.02 % 99.0l TMP
Recovery 73 ~ 68 ~ 66 ~ 9l '~VO94/0783l '~ 11'3 ''~ PCT/US93/08140 Example 3 A batch aldol reaction was performed in glassware as follows:
n-Butyraldehyde (600.0 g, 8.32 mol)~
paraformaldehyde (686.4 g, 20.80 mol), water (74.31 g, 4.12 mol), and triethylamine (42.1 g, 0.42 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 50C. The bath was heated to a temperature of 80C over a period of 2 hours at which point 99% of the n-butyraldehyde was reacted.
The reaction mixture was diluted to make a 50 wt %
aldol in 2-methyl-1-butanol solution. A continuous hydrogenation was performed by passing the aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr 1 LHSV, and 1000 psig H2. The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.49% purity, 72% recovery).
The results obtained from this experiment, when compared to Example lA., show similar distilled TMP purity and recovery using a different indigenous alcoholic solvent, 2-methyl-1-butanol (Table III).
W O 94/07831 PCT/US93/0814~`
~ "3 -14-Sabl- ~SS
Example lA. 3.
-HCHO p~r~torm- p~r~for~-~yp- ~ld-hyd~ ~ldehyde Added Solvent meth~nol 2-met~yl-1-butanol ;.
Solvent Level (wt %) 50 % 50 %
~ .
Distilled T~P
Purity (wt %) 99.18 % 99.49 %
:
TMP
Recovery 73 ~ 72 ~ `
.
-vo 94/07831 P~r/US93/08140 2 ~ 2 1 ~
Example 4 A batch aldol reaction was performed in ~lassware as follows:
n-Butyraldehyde (772.4 g, 10.71 mol), aqueous formaldehyde (2173.4 g, 26.78 mol), and triethy~amine (54.2 g, 0.54 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 40C. The bath was heated to a temperature of 60C over a period of 2 hours at which point >99%
of the n-butyraldehyde was reacted. A continuous hydrogenation was performed by passing the undiluted --aldol effluent upward through a f ixed-bed of stabilized copper chromite at 160C, 0.5 hr 1 LHSV, and 1000 psig H2. The resultant hydrogenation product was diluted in methanol to make a 50 wt %
solution and batch distilled using an 8-inch long packed column to recover trimethylolpropane product (98.92% purity, 68% recovery).
The result obtained from this experiment, when compared to Example lD., (the "controll' experiment using alcoholic solvent was not added prior to hydrogenation or distillation), shows an improved distilled TMP purity at a similar recovery.
However, the product purity was not guite as high when the alcoholic solvent was added to the aldol effluent prior to hydrogenation (such as shown in Example lA. or Example 3.) which is our most preferred mode. These results are displayed together in Table IV.
W O 94/07831 PCT/VS93/0814r 2 1 ~ 3 -16-~bl- IV
-Ex~mple lA. lD. 3. 4.
(~control~) NCHO p~r~for~- equeou~ p~r~Sor~- ~queou5 Type alde~yde form~lde~yae ~ldebyde form~lde~yde Added Solvent met~nol none 2-met~yl~ ~et~nol l-but~nol (~fter bydrogen-~tion~ -:, Solvent Level ::
(wt %) 50 % 5 % 50 % 50 t (cont~ined) (~fter hydrogen-~tion) Distilled TMP
Purity (wt %~ 99.18 % 98.33 % 99.49 % 98.92 qMP
Rscovery 73 % 73 % 72 ~ 68 -~V094/07831 ~ ? ~ PCT/US93/08140 --Example 5 A batch aldol reaction was performed in glassware as follows:
n-Butyraldehyde (960.0 g, 13.31 mol), paraformaldehyde (1098.3 9, 33.28 mol), water (111.3 g, 6.17 mol) and triethylamine (67.4 g, 0.67 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lQwered into a water bath at 50C. The bath was ~:
heated to a temperature of 80C over a period of 1 -hour and continued for an additional hour at which point 98% of the n-butyraldehyde was reacted. The reaction mixture was diluted in isopropyl alcohol (IPA) to make a 50 wt ~ solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr~1 LHSV, and 1000 ~sig H2. The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.29% purity, 70%
recovery).
The data for this experiment, when compared to Example lA. and Example lB., show similar TMP distilled purities (>99%) in ~ood recoveries using a 2 alcohol as solvent. These results are shown in Table V.
W O 94/07831 PCT/US93/0814~-.
~able V
Example lA. lB. V.
HCHO paraform- aqueous paraform- ;
~- Type aldehyde formaldehyde alclehyde Added isopropyl Solvent methanol metbanol alc:obol Solvent Level (wt ~) 50 % 50 % 50 %
.
Di tilled TMP
Purity (wt %) 99.18 % 99.07 ~ 99.29 %
TMP
Recovery 73 ~ 68 % 70 % .
_ . _ _ _
Technical Field This invention relates to the production of trimethylolpropane and particularly to conducting the hydrogenation of the reaction product of n-butyraldehyde ( NBAL) and formaldehyde in the presence of at least 20% of a lower alcohol of the formula RlR2CHOH where R1 and R2 are independently hydrogen or alkyl groups having 1 to about 5 carbon -atoms but together have no more than 6 carbon atoms.
Background of the Invention The conventional production of trimethylolpropane typically entails the reaction of n-butyraldehyde and formaldehyde ~usually an aqueous solution~ to obtain the aldol reaction product which may then be hydrogenated over a hydrogenation catalyst either with or without treatment intended to purify it. Representative of the prior art are U.S~ Patents 4,122,290 and 4,514,578 to Immel et al and 4,594,461 to Merger et al, which may use a trialkyl-amine catalyst in the aldol step. While the conventional commercial processes have served more or less satisfactorily in the context of the state of the art, our process is much more efficient and the product is much more pure.
Commercially, formaldehyde is available in either of two forms, paraformaldehyde or as an WO94/07831 PCT/US93/0814~-2 l ~ 8 3 aqueous solution ~referred to herein as aqueous formaldehyde). Paraformaldehyde is a crystalline solid consisting of a linear polymeric form of formaldehyde of the molecular formula, HO(CH2)nH
where n - 8-100. Aqueous formaldehyde consists predominently as formaldehyde in its monomeric form.
On standing, it will gradually react with itself forming oligomeric formaldehyde and paraformaldehyde. This is commonly inhibited by sdding up to 15% methanol as a stabilizer. Where "formaldehyde" is used hereafter, we mean that either formaldehyde in the form of paraformaldehyde or aqueous formaldehyde is acceptable unless otherwise specified.
K}ein, in U.S. Patent 3,076,854, treats a crude trimethylolpropane by solvent extracting with an alcohol such as amyl alcohol, re-extracting with water, heating with methanol in the presence of a strong acid, and passinq through an ion exchange bed to remove metals. Purification was not accomplished by distillation as in the present invention.
In East German Patent 142,184, Dietze et al follow a more or less conventional TMP
preparation by distillation to obtain a distillation bottoms comprising about 3% of the reaction product;
this bottoms portion is treated with methanol and passed through a strong acid resin to liberate additional TMP.
Merger et al, in European Patent 289,921, treat the hydroqenated effluent of the trialkylamine catalyzed reaction of n-butyraldehyde and aqueous formaldehyde in one of two ways. In the first they ~094/07831 ~ PCT/US93/08140 remove water and excess trialkylamine by distillation at 100-200C. Trialkylamine which is tied up as its formate salt reacts with trimethylolalkane under distillation conditions to give free trialkylamine and formate esters of the polyol. They then add methanol and either an alcoholate of an alkalai or alkaline earth metal to liberate the trimethylolalkane which is recovered by distillation. The second method involves removal of ~-the excess water and free trialkylamine by distillation followed by the addition of methanol to the distillation bottoms. This mixture is then heated to 100-200C under pressure, and trialkylamine and methylformate are removed by distillation. The water concentration in ~his instance is quite stringent and can be no more than 5-15%. While the product is finally recovered by distillation, no mention is made of purity.
Our process does not require any special treatment before alcohol addition and leads to a product of very high purity.
Raue et al, in Example 1 of East German Patent 273,434, describe a process for recovering formaldehyde from the Ca(OH)2 catalyzed reaction of higher aldehydes with formaldehyde to form polymethylolalkanes. The treatment first requires neutralization of the reaction effluent followed by addition of methanol, stripping of lights at 50C
under vacuum, treating with acetonitrile, removing calcium salts, addinq additional methanol and stripping up to 90C to remove lights includinq g formaldehyde. No mention is made of product recovery. Our process is simple, different, and leads to high purity TMP.
Summary of the Invention Our process involves an aldol reaction of n-butyraldehyde and formaldehyde followed directly by a hydrogenation step conducted in the presence of at least about 20% by weight lower alcohol of the formula RlR2CHOH where Rl and R2 are independently hydrogen or alkyl groups having l to about 5 carbon atoms but together have no more than 6 carbon atoms.
In the hydrogenation step the catalyst, preferably copper chromite, is used at temperatures in the range of about 100C to about 200C, and relatively low pressures, in the range of 500 to about 3000 psi. Our invention will give good yields of desired product, having very high purity, as will become apparent in the section below.
To make the hydrogenation feed, the n-butyraldehyde and the formaldehyde should be employed in molar ratios of about 0.5 to about l0, preferably 0.5 to 5 and most preferably about l to about 2.5.
We prefer to use a hydrogenation feed containing 20 to 90% alcohol, preferably 30-60%
alcohol, and most preferably 50% alcohol; the preferred alcohol is methanol. The alcohol may be added after hydrogenation; however, the most benefit is derived from adding the alcohol prior to hydrogenation, which is our preferred mode.
`~094/07831 2 1 2 ~ 3 PCT/US93/08140 Detailed Description of the Invention Our invention will be described with particular attention to the examples below.
SPecific Procedure usinq Paraformaldehvde I ;
A specific reaction using paraformaldehyde ~
may be described as follows: The reaction is -performed in a reflux apparatus wherein l.00 equivalent of NBAL, 2.50 equivalents of -paraformaldehyde, and about 0.04 to 0.05 equivalents of triethylamine have been placed under an inert atmosphere. With overhead stirrin~, the reaction mixture is heated, initially, in a water bath at 50C; the temperature is gradually increased to 80~C
over a one-hour period. The reaction is continued for an additional hour and terminated. The clear molten liquid is diluted in an alcohol, preferably methanol, and hydrogenated by passing the reaction solution over a conventional copper chromite catalyst at about 160C and about l000 psi ~2 High purity TMP product (>99%) is recovered in good yield by distillation.
Specific ~rocedure usinq Aqueous Formaldehyde Another specific reaction using agueous formaldehyde may be described as follows: The reaction is performed in a reflux apparatus wherein l.00 equivalent of NBAL, 2.50 equivalents of aqueous formaldehyde, and about 0.04 to 0.08 equivalents of triethylamine have been placed under an inert atmosphere. Preferably the NBAL is added dropwise WO94/07831 PCT/US93/08~4 3~ ~?~ a over a 0.25-1 hour period to the stirred mixture of aqueous formaldehyde and triethylamine. With overhead stirring, the reaction mixture is heated in a water bath at 60C for two hours. The clear liquid is diluted in an alcohol preferably methanol and hydroqenated by passing the reaction solution over a conventional copper chromite catalyst at about 160C and about 1000 psi. High purity TMP product (>99%) is recovered in good yield by distillation.
General Procedure usinq Formaldeh~de More generally, with 1 equivalent of NBAL
we may place in a reaction vessel from about 2 to about 10 equiv~alents of formaldehyde and about 0.001 to about 1.0 (preferably about 0.05 to about 0.5) equivalent of a tertiary amine catalyst. The reaction mixture is stirred at 60-80C until most of the NBAL is consumed. The resulting solution is diluted in an alcohol preferably methanol and hydrogenated using a hydrogenatinn catalyst. High purity TMP product is obtained in good yield by distillation.
Example 1 ~ series of batch aldol reactions were performed in glassware as follows:
A. n-Butyraldehyde (1069.3 g, 14.89 mol), paraformaldehyde (1223.4 g, 37.07 mol), water (132.4 g, 7.35 mol)~ and triethylamine t75.0 g, 0.74 mol) were added into a 3-neck roundbottom flask -W O 94/07831 2 1 .~ PC~r/US93/08140 equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was placed in a water bath at 50C. The bath was heated to a temperature of 80C over a period of 2 hours at which point >99% of the n-butyraldehyde was reacted.
The reaction mixture was diluted in methanol to make a 50 wt % aldol in methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of copper chromite at 160C, 0.5 hr 1 liquid hour space velocity (LHSV), and 1000 psig H2. The resultant hydrogenation product was batch, distilled ~' using an 8-inch long packed column to recover high puritr trimethylolpropane product (99.18% purity, ' 73.3% recovery).
B. n-Butyraldehyde (643.7 g, 8.93 mol), aqueous formaldehyde (1811.2 9, 22.32 mol), and triethylamine ~45.2 5, 0.45 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 40C. The bath was heated to a temperature of 60C over a period of 1 hour and continued for an additional hour at which point 97% of the n-butyraldehyde was reacted. The reaction mixture was diluted in methanol to make a 50 wt % aldol in methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr LHSV, and 1000 psig H2.
The`resultant hydrogenation product was batch WO94/07831 PCT/US93/0814r ~ :1 2 ~ 3 ~ ' :
distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.07% purity, 68.4% recovery).
C. Example l.A. was repeated except that the aldol reaction mixture was diluted in n-butyl alcohol rather than methanol to make a 50 wt % aldol in n-butyl alcohol solution. High purity trimethylolpropane product was obtained (99.15%
purity, 72.3% recovery).
D. The "controlN experiment was performed by repeating Example l.B. without adding the methanol solvent prior to hydrogenation. The trimethylolpropane produst recovered was of lower purity~(98.33% purity, 73.0% recovery).
The data for these four experiments are summarized in Table I. The results reveal the surprising improvement in trimethylolpropane purity made possible by the addition of a suitable alcohol solvent to aldol reaction product prior to hydroqenation.
~vo 94/07831 '~ ,'?~ PCT/US93/08140 Table I :~
Exa~ple lA. lB. ~C. lD.(Ucontrol~) HC~ paraform- aqueous paraform- aqueous 5ype aldehyde formaldehyde aldehyde formaldehyde ~dded n-butyl 5Olvent ~Pt~nol ~t~an51 ~leobo~ none So~ve~t Le~el 0 ~ 50 ~ 50 % S S
~ cor~t~lnod) Di~tilled ~us~ty %) 99.18 ~ 9~.0~ ~ 99~5 ~ 98.3 ~ecovery 73 4 ~ ~ 7~ ~ 7~ g WO9~/07831 PCT/US93/0814~
~ ~ 2 ïl~9 ExamPle 2 Two batch aldol reactions were performed in glassware as follows:
A. n-Butyraldehyde (772.4 g, 10.71 mol), aqueous formaldehyde (2173.4 g, 26.78 mol)~ and triethylamine (54.2 g, 0.54 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 40C. The bath was heated to a temperature of 60C over a period of 2 hours at which point >99%
of the n-butyraldehyde was reacted. The reaction mixture was diluted in methanol to make a 9~ wt methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr 1 LHSv, and 1000 psig H2.
The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.02~ purity, 66% recovery).
B. n-Butyraldehyde (943.4 g, 13.08 mol), paraformaldehyde (1079.3 g, 33.71 mol), water (116.8 g, 6.48 mol) and triethylamine (66.2 g, 0.65 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 50~C. The bath was heated to a temperature of 80C over a period of 1 hour and continued for an additional hour at which point 99% of the n-butyraldehyde was reacted. The reaction mixture was diluted in methanol to make a ~':
:
'~/094/07831 ~,~ 2 ;1 i ~ ~ PCT/US93/08140 20 wt % methanol solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr l LHSV, and lO00 psig H2. The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.01% purity, 91%
recovery).
The data for these two experiments, when ::: compared to Example lA. and Example lB., show similar TMP distilled purities (>99%) in good '`
recoveries using higher (90 wt %) and lower (20 wt %) methanol levels. These results are displayed in Table II.
~.
W O 94/07831 PCT/US93/0814~-S~bl- ~I
Ex~plelA. 1~. 2A. 2EI.
HCHOparaform- aqu~ous equ~ou~ paraform-Type aldehyde roraaldebyde formalde~yde aldehyde Added ~olvent ~ethanol ~et~anol ~ethanol ~et~anol .
Solvent Level (wt %) 50 % 50 % 90 % 20 %
.
Distilled TMP
Purity (wt %) 99.~8 ~ 99.0~ % 99.02 % 99.0l TMP
Recovery 73 ~ 68 ~ 66 ~ 9l '~VO94/0783l '~ 11'3 ''~ PCT/US93/08140 Example 3 A batch aldol reaction was performed in glassware as follows:
n-Butyraldehyde (600.0 g, 8.32 mol)~
paraformaldehyde (686.4 g, 20.80 mol), water (74.31 g, 4.12 mol), and triethylamine (42.1 g, 0.42 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 50C. The bath was heated to a temperature of 80C over a period of 2 hours at which point 99% of the n-butyraldehyde was reacted.
The reaction mixture was diluted to make a 50 wt %
aldol in 2-methyl-1-butanol solution. A continuous hydrogenation was performed by passing the aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr 1 LHSV, and 1000 psig H2. The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.49% purity, 72% recovery).
The results obtained from this experiment, when compared to Example lA., show similar distilled TMP purity and recovery using a different indigenous alcoholic solvent, 2-methyl-1-butanol (Table III).
W O 94/07831 PCT/US93/0814~`
~ "3 -14-Sabl- ~SS
Example lA. 3.
-HCHO p~r~torm- p~r~for~-~yp- ~ld-hyd~ ~ldehyde Added Solvent meth~nol 2-met~yl-1-butanol ;.
Solvent Level (wt %) 50 % 50 %
~ .
Distilled T~P
Purity (wt %) 99.18 % 99.49 %
:
TMP
Recovery 73 ~ 72 ~ `
.
-vo 94/07831 P~r/US93/08140 2 ~ 2 1 ~
Example 4 A batch aldol reaction was performed in ~lassware as follows:
n-Butyraldehyde (772.4 g, 10.71 mol), aqueous formaldehyde (2173.4 g, 26.78 mol), and triethy~amine (54.2 g, 0.54 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lowered into a water bath at 40C. The bath was heated to a temperature of 60C over a period of 2 hours at which point >99%
of the n-butyraldehyde was reacted. A continuous hydrogenation was performed by passing the undiluted --aldol effluent upward through a f ixed-bed of stabilized copper chromite at 160C, 0.5 hr 1 LHSV, and 1000 psig H2. The resultant hydrogenation product was diluted in methanol to make a 50 wt %
solution and batch distilled using an 8-inch long packed column to recover trimethylolpropane product (98.92% purity, 68% recovery).
The result obtained from this experiment, when compared to Example lD., (the "controll' experiment using alcoholic solvent was not added prior to hydrogenation or distillation), shows an improved distilled TMP purity at a similar recovery.
However, the product purity was not guite as high when the alcoholic solvent was added to the aldol effluent prior to hydrogenation (such as shown in Example lA. or Example 3.) which is our most preferred mode. These results are displayed together in Table IV.
W O 94/07831 PCT/VS93/0814r 2 1 ~ 3 -16-~bl- IV
-Ex~mple lA. lD. 3. 4.
(~control~) NCHO p~r~for~- equeou~ p~r~Sor~- ~queou5 Type alde~yde form~lde~yae ~ldebyde form~lde~yde Added Solvent met~nol none 2-met~yl~ ~et~nol l-but~nol (~fter bydrogen-~tion~ -:, Solvent Level ::
(wt %) 50 % 5 % 50 % 50 t (cont~ined) (~fter hydrogen-~tion) Distilled TMP
Purity (wt %~ 99.18 % 98.33 % 99.49 % 98.92 qMP
Rscovery 73 % 73 % 72 ~ 68 -~V094/07831 ~ ? ~ PCT/US93/08140 --Example 5 A batch aldol reaction was performed in glassware as follows:
n-Butyraldehyde (960.0 g, 13.31 mol), paraformaldehyde (1098.3 9, 33.28 mol), water (111.3 g, 6.17 mol) and triethylamine (67.4 g, 0.67 mol) were added into a 3-neck roundbottom flask equipped with an overhead stirrer, inert atmosphere purge, and a reflux condenser. The apparatus was lQwered into a water bath at 50C. The bath was ~:
heated to a temperature of 80C over a period of 1 -hour and continued for an additional hour at which point 98% of the n-butyraldehyde was reacted. The reaction mixture was diluted in isopropyl alcohol (IPA) to make a 50 wt ~ solution. A continuous hydrogenation was performed by passing the methanolic aldol effluent upward through a fixed-bed of stabilized copper chromite at 160C, 0.5 hr~1 LHSV, and 1000 ~sig H2. The resultant hydrogenation product was batch distilled using an 8-inch long packed column to recover high purity trimethylolpropane product (99.29% purity, 70%
recovery).
The data for this experiment, when compared to Example lA. and Example lB., show similar TMP distilled purities (>99%) in ~ood recoveries using a 2 alcohol as solvent. These results are shown in Table V.
W O 94/07831 PCT/US93/0814~-.
~able V
Example lA. lB. V.
HCHO paraform- aqueous paraform- ;
~- Type aldehyde formaldehyde alclehyde Added isopropyl Solvent methanol metbanol alc:obol Solvent Level (wt ~) 50 % 50 % 50 %
.
Di tilled TMP
Purity (wt %) 99.18 % 99.07 ~ 99.29 %
TMP
Recovery 73 ~ 68 % 70 % .
_ . _ _ _
Claims (15)
1. Method of making high purity trimethylolpropane comprising reacting n-butyraldehyde and formaldehyde under aldol reaction conditions and hydrogenating the reaction product in the presence of at least about 20 wt %
(based on the mixture of alcohol and said reaction product) of an alcohol of the formula R1R2CHOH where R1 and R2 are independently selected from hydrogen and alkyl groups having 1 to about 5 carbon atoms but together have no more than 6 carbon atoms.
(based on the mixture of alcohol and said reaction product) of an alcohol of the formula R1R2CHOH where R1 and R2 are independently selected from hydrogen and alkyl groups having 1 to about 5 carbon atoms but together have no more than 6 carbon atoms.
2. Method of claim 1 wherein the hydrogenation is conducted in the presence of a copper chromite catalyst.
3. Method of claim 1 wherein the hydrogenation is conducted at a pressure in the range of about 500 to about 3000 psig.
4. Method of claim 1 wherein the alcohol comprises methanol.
5. Method of claim 1 wherein the aldol reaction step is conducted in the presence of a catalyst comprising an amine of the formula R1R2R3N
wherein R1, R2 and R3 are independently selected from alkyl and aryl groups having from 1 to 5 carbon atoms and R1 and R2 may form a substituted or unsubstituted cyclic group having about 5 to about 10 carbon atoms.
wherein R1, R2 and R3 are independently selected from alkyl and aryl groups having from 1 to 5 carbon atoms and R1 and R2 may form a substituted or unsubstituted cyclic group having about 5 to about 10 carbon atoms.
6. Method of claim 5 wherein the aldol reaction step is conducted in the presence of a triethylamine catalyst.
7. Method of claim 1 wherein the formaldehyde is in the form of paraformaldehyde.
8. Method of claim 1 wherein the formaldehyde is in the form of aqueous formaldehyde.
9. Method of claim 1 wherein trimethylolpropane of greater than 99% purity is recovered by distillation.
10. Method of claim 1 wherein the hydrogenation step is conducted at a temperature of about 100°C to about 200°C.
11. Method of claim 1 wherein the molar ratio of n-butyraldehyde to formaldehyde in the aldol reaction is about 1:2 to about 1:5.
12. Method of claim 4 wherein the methanol is present in an amount from about 30% to about 60% of the hydrogenation feed.
?O 94/07831 PCT/US93/08140
?O 94/07831 PCT/US93/08140
13. Method of making trimethylolpropane comprising reacting n-butyraldehyde and formaldehyde under aldol conditions, hydrogenating the reaction product thereof, adding to said reaction product at least about 20% by weight of an alcohol of the formula R1R2CHOH where R1 and R2 are independently selected from hydrogen and alkyl groups having 1 to about 5 carbon atoms but together have no more than about 6 carbon atoms, and distilling the resulting mixture to obtain a high purity trimethylolpropane.
14. Method of claim 13 wherein the alcohol is added to the hydrogenated reaction product in an amount between about 20% by weight and about 90% by weight of the mixture after such addition.
15. Method of claim 13 wherein the alcohol is methanol.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US95052492A | 1992-09-25 | 1992-09-25 | |
US950,524 | 1992-09-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
CA2124189A1 true CA2124189A1 (en) | 1994-04-14 |
Family
ID=25490541
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA 2124189 Abandoned CA2124189A1 (en) | 1992-09-25 | 1993-08-27 | Manufacture of trimethylolpropane |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0614453A4 (en) |
JP (1) | JPH07501561A (en) |
CA (1) | CA2124189A1 (en) |
WO (1) | WO1994007831A1 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19542036A1 (en) * | 1995-11-10 | 1997-05-15 | Basf Ag | Process for the preparation of polyalcohols |
US6034284A (en) * | 1997-10-22 | 2000-03-07 | Koei Chemical Company, Limited | Producing method for trimethylolalkane |
JP4669097B2 (en) * | 1999-12-28 | 2011-04-13 | 日本曹達株式会社 | Post-treatment method for reaction using Lewis acid |
KR100837523B1 (en) * | 2006-03-07 | 2008-06-12 | 주식회사 엘지화학 | Method for Preparing Trimethylolpropane |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1014089B (en) * | 1956-05-05 | 1957-08-22 | Basf Ag | Process for the preparation of 2,2-dimethylpropanediol- (1,3) |
FR1230558A (en) * | 1959-03-31 | 1960-09-16 | Ets Kuhlmann | Process for preparing neo-pentyl-glycol |
DE2054601C3 (en) * | 1970-11-06 | 1980-02-14 | Ruhrchemie Ag, 4200 Oberhausen- Holten | Process for the preparation of dihydric alcohols |
DE2702582C3 (en) * | 1977-01-22 | 1980-12-04 | Bayer Ag, 5090 Leverkusen | Process for the preparation of trimethylolalkanes |
DE3340791A1 (en) * | 1983-11-11 | 1985-05-23 | Basf Ag, 6700 Ludwigshafen | METHOD FOR PRODUCING TRIMETHYLOLALCANES FROM ALKANALS AND FORMALDEHYDES |
DE3644675A1 (en) * | 1986-12-30 | 1988-07-14 | Ruhrchemie Ag | METHOD FOR PRODUCING 2,2-DIMETHYLPROPANDIOL- (1,3) |
US4855515A (en) * | 1987-08-12 | 1989-08-08 | Eastman Kodak Company | Process for the production of neopentyl glycol |
US5144088A (en) * | 1991-04-26 | 1992-09-01 | Aristech Chemical Corporation | Manufacture of neopentyl glycol (I) |
US5185478A (en) * | 1991-06-17 | 1993-02-09 | Aristech Chemical Corporation | Manufacture of neopentyl glycol (IIA) |
-
1993
- 1993-08-27 EP EP19930920413 patent/EP0614453A4/en not_active Withdrawn
- 1993-08-27 WO PCT/US1993/008140 patent/WO1994007831A1/en not_active Application Discontinuation
- 1993-08-27 JP JP6509052A patent/JPH07501561A/en active Pending
- 1993-08-27 CA CA 2124189 patent/CA2124189A1/en not_active Abandoned
Also Published As
Publication number | Publication date |
---|---|
EP0614453A4 (en) | 1994-09-21 |
EP0614453A1 (en) | 1994-09-14 |
WO1994007831A1 (en) | 1994-04-14 |
JPH07501561A (en) | 1995-02-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6187971B1 (en) | Method for producing polyalcohols | |
EP0522368B2 (en) | Manufacture of neopentyl glycol (IV) | |
KR101584375B1 (en) | Process for preparing polyalcohols from formaldehyde with a low formic acid content | |
KR960004879B1 (en) | Triethylamine catalyzed neophenyl glycol production utilizing a gas sparged reactor | |
US4190601A (en) | Production of tertiary amines by reductive alkylation | |
US7301058B2 (en) | Method for increasing yield in the production of polyvalent alcohols by splitting by-products containing acetal | |
KR100694344B1 (en) | Method of producing highly pure trimethylolpropane | |
US5532417A (en) | Manufacture of neopentyl glycol (IV) | |
EP0522367B1 (en) | Manufacture of neopentyl glycol (III) | |
KR100478318B1 (en) | Ester co-production | |
US5763690A (en) | Manufacture of trimethylolpropane | |
CA2124189A1 (en) | Manufacture of trimethylolpropane | |
EP0429603B1 (en) | Preparation of unsaturated ketones | |
US6441254B1 (en) | Process for preparing trimethylol compounds and formic acid | |
US5185478A (en) | Manufacture of neopentyl glycol (IIA) | |
KR20020062666A (en) | Method for The Decomposition of High Boiling By-Products Produced in The Synthesis of Polyhydric Alcohols | |
KR20020001600A (en) | Process for producing a polyol | |
EP0543970B1 (en) | Manufacture of neopentyl glycol (iia) | |
US5166450A (en) | Production of hydroxyketones | |
KR20020064670A (en) | Production of dimethylolcarboxylic acid | |
US6316664B1 (en) | Process for preparing hydroxy-containing compounds from formic acid esters | |
JPH05117187A (en) | Process for manufacturing neopentyl glycol | |
JPH1059892A (en) | Production of alpha,beta-unsaturated aldehyde | |
JPH069513A (en) | Production of alkylaminophenols | |
JPH0262836A (en) | Production of 2-n-butyl-2-ethyl-1,3-propanediol |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FZDE | Dead |