Manufacture of neopentyl glycol (IV)

• US 5,532,417 A
• Filed: 08/02/1993
• Issued: 07/02/1996
• Est. Priority Date: 04/26/1991
• Status: Expired due to Term

• Current Assignee: BASF Corporation (BASF SE)
• Original Assignee: Aristech Chemical Corporation (Energy Transfer Operating, L.P.)
• Inventors: Pugach, Joseph, Salek, Jeffrey S., Elias, Carole L., Cullo, Leonard A.
• Primary Examiner(s): Cook, Rebecca
• Application Number:
  US08/100,356
• Time in Patent Office: 1,065 Days
• Field of Search: 568/464, 568/862, 568/853
• US Class Current: 568/853
• CPC Class Codes: C07C 29/141 with hydrogen or hydrogen-containing gases
• CPC Class Codes: C07C 29/38 by reaction with aldehydes or ketones
• CPC Class Codes: C07C 31/20 Dihydroxylic alcohols
• CPC Class Codes: C07C 45/75 Reactions with formaldehyde
• CPC Class Codes: C07C 47/19 containing hydroxy groups sugars C07H

Abstract

Neopentyl glycol is made from isobutyraldehyde and formaldehyde. The formaldehyde may be in the form of paraformaldehyde or aqueous formaldehyde. The aldol reaction product is mixed with a lower alcohol prior to hydrogenation to promote hydrogenolysis and 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.

Claims

1. Method of making neopentyl glycol comprising hydrogenating the aldol reaction product of formaldehyde and isobutyraldehyde in the liquid phase at a pressure of about 500-3000 psig, and in the presence of a hydrogenation catalyst and at least about 20 wt % based on the mixture of alcohol and the reaction product, of an alcohol of the formula RR'"'"'CHOH wherein R and R'"'"' are independently selected from hydrogen and alkyl groups having from one to five carbon atoms and have a total of no more than five carbon atoms, said hydrogenation including the hydrogenolysis of 3-hydroxy-2,2-dimethylpropyl hydroxypivalate and the hydrogenation of hydroxypivaldehyde present in said reaction product.

2. Method of claim 1 wherein the formaldehyde is in the form of paraformaldehyde.

3. Method of claim 1 wherein the formaldehyde is aqueous formaldehyde.

4. Method of claim 1 wherein the reaction of isobutyraldehyde and formaldehyde is conducted in the presence of a catalyst comprising an amine of the formula R¹ R² R³ N where R¹, R², and R³ are independently selected from alkyl and aryl groups having from one to five carbon atoms and R¹ and R² may form a substituted or unsubstituted cyclic group having about 5 to about 10 carbon atoms.

5. Method of claim 1 wherein the alcohol is methanol.

6. Method of claim 1 wherein the hydrogenation reaction is conducted at a temperature of about 100°

C. to about 200°

C.

7. Method of claim 1 wherein the reaction of isobutyraldehyde with formaldehyde employs a molar ratio of formaldehyde relative to isobutyraldehyde of about 0.5:

1 to 2;

1.

8. Method of claim 1 wherein the alcohol content of the alcohol-reaction product mixture is no greater than 90% by weight and water is present in an amount no greater than 40% by weight based on the total of reaction product, alcohol and water.

9. Method of claim 1 wherein the alcohol is recovered, the neopentyl glycol is recovered, and the alcohol is recycled.

10. Method of claim 1 wherein the hydrogenation catalyst comprises copper chromite.

11. Method of claim 1 wherein the neopentyl glycol is recovered by distillation.

13. Method of claim 1 wherein the alcohol is present during the hydrogenation reaction in an amount of about 50% by weight of the mixture with aldol reaction product and water is present in an amount from about 1% to about 15% by weight.

12. Method of claim i wherein the alcohol is present during the hydrogenation reaction in an amount from about 30% to about 60% by weight of the mixture with aldol reaction product and water is present in an amount from about 0% to about 20% by weight.