Production of neopentane

Patent metadata

Field	Value
Publication number	US-10870610-B2
Application number	US-201716324788-A
Country	US
Kind code	B2
Filing date	Aug 18, 2017
Priority date	Aug 29, 2016
Publication date	Dec 22, 2020
Grant date	Dec 22, 2020

Abstract

Disclosed herein are processes for producing neopentane. The processes generally relate to demethylating isooctane to produce neopentane. The isooctane may be provided by the alkylation of isobutane with butylenes.

First claim

What is claimed is:

1. A process for producing neopentane, the process comprising:
(a) contacting isobutane with butylenes under alkylation conditions effective to produce an alkylation product comprising isooctane; and
(b) demethylating the isooctane by contacting the isooctane with hydrogen at a temperature of from 200 to 500° C., a hydrogen partial pressure of about 7 psia to about 500 psia, and in the presence of a catalyst comprising at least one member selected from the group consisting of Fe, Co, Ni, Rh, Jr, Ru, Pt, Pd, combinations thereof, compounds thereof, and mixtures of compounds thereof, to produce a demethylation product comprising at least 10 wt % neopentane based on the weight of the demethylation product, wherein the catalyst further comprises at least one member selected from the group consisting of Cu, Au, Ag, Sn, Zn, Re, combinations thereof, compounds thereof, and mixtures of compounds thereof.

2. The process of claim 1 , wherein at least part of the isooctane is separated from the alkylation product prior to demethylation.

3. The process of claim 2 , wherein separating the isooctane from the alkylation product comprises distillation.

4. The process of claim 3 , wherein the alkylation product is separated into fractions comprising (1) an unreacted isobutane fraction, (2) an isooctane fraction, and (3) a non-isooctane C 8+ hydrocarbon fraction.

5. The process of claim 4 , wherein the contacting is carried out in a reaction vessel, and wherein the unreacted isobutane fraction is recycled to the reaction vessel.

6. The process of claim 1 , wherein the butylenes are provided in a raffinate stream obtained from cracking a naphtha stream.

7. The process of claim 1 , wherein the contacting is carried out in the presence of a catalyst (A) comprising sulfuric acid, hydrofluoric acid, or mixtures thereof.

8. The process of claim 7 , further comprising washing the alkylation product with water.

9. The process of claim 7 , wherein the contacting is carried out at a temperature ranging from about 0° C. to about 50° C. and wherein the molar ratio of isobutane to butylenes supplied to the contacting ranges from about 10:1 to about 75:1.

10. The process of claim 1 , wherein the contacting is carried out in the presence of a catalyst (B) selected from the group consisting of chlorided alumina, fluorided alumina, acidic metal oxide, acidic mixed metal oxide, zeolites, and mixtures thereof.

11. The process of claim 10 , wherein the contacting is carried out at a temperature ranging from about 100° C. to about 400° C. and wherein the molar ratio of isobutane to butylenes supplied to the contacting ranges from about 50:1 to about 200:1.

12. The process of claim 1 , further comprising separating at least part of the neopentane from the demethylation product.

13. The process of claim 12 , wherein separating the neopentane from the demethylation product comprises distillation.

14. The process of claim 13 , wherein the demethylation product is separated into fractions comprising (1) a C 4− hydrocarbon fraction, (2) a neopentane fraction, and (3) a C 6+ hydrocarbon fraction.

15. The process of claim 14 , wherein the demethylation is carried out in a reaction vessel, and wherein the C 6+ hydrocarbon fraction is recycled to the reaction vessel.

16. The process of claim 1 , wherein the catalyst (C) comprises a support material selected from the group consisting of silica, theta-alumina, clay, pentasil, aluminophosphate, carbon, titania, zirconia, and mixtures thereof.

17. The process of claim 1 , wherein the demethylation is carried out under conditions comprising at least one of a temperature from about 220° C. to about 300° C., a pressure from about 15 psig to about 200 psig (about 205 kPa absolute to about 1400 kPa absolute), or a hydrogen to hydrocarbon molar ratio from about 1:1 to about 14:1.

18. The process of claim 1 , wherein the demethylation product comprises from about 25 wt % to about 50 wt % neopentane based on the weight of the demethylation product and from about 0 wt % to about 10 wt % C 6+ hydrocarbon components based on the weight of the demethylation product.

19. A process for producing neopentane, the process comprising:
(a) providing a stream comprising isooctane; and
(b) demethylating the isooctane by contacting the isooctane with hydrogen at a temperature of from 200 to 500° C., a hydrogen partial pressure of about 7 psia to about 500 psia, and in the presence of a catalyst comprising at least one member selected from the group consisting of Fe, Co, Ni, Rh, Ir, Ru, Pt, Pd, combinations thereof, compounds thereof, and mixtures of compounds thereof, to produce a demethylation product comprising at least 10 wt % neopentane based on the weight of the demethylation product, wherein the catalyst further comprises at least one member selected from the group consisting of Cu, Au, Ag, Sn, Zn, Re, combinations thereof, compounds thereof, and mixtures of compounds thereof.

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Wang Kun
• Decaul Lorenzo C
• Levine Steven W
• Mazoyer Etienne
• Lattner James R
• Jaensch Helge
• Kheir Ali A

Classifications

• C07C4/10 Primary

  from acyclic hydrocarbons · CPC title

• C07C2523/58

  with alkali- or alkaline earth metals or beryllium · CPC title

• C09K5/00

  Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion · CPC title

• C08J9/141

  Hydrocarbons · CPC title

• C07C2/58

  Catalytic processes · CPC title