Process for forming propylene oxide from oxidation of methyl benzyl alcohol

Patent metadata

Field	Value
Publication number	US-2016297783-A1
Application number	US-201615093370-A
Country	US
Kind code	A1
Filing date	Apr 7, 2016
Priority date	Apr 9, 2015
Publication date	Oct 13, 2016
Grant date	—

Abstract

The present disclosure relates to a method of preparing propylene oxide comprising the steps:
(a) oxidizing alpha-methylbenzyl alcohol with air to form a first reaction mixture comprising hydrogen peroxide and acetophenone; (b) reacting propylene with the first reaction mixture in the presence of a catalyst to form a second reaction mixture comprising propylene oxide; (c) separating the propylene oxide from the second reaction mixture to form a third reaction mixture; (d) heating the third reaction mixture to decompose hydrogen peroxide, whereby a fourth reaction mixture is formed; (e) hydrogenating the acetophenone in the fourth reaction mixture with hydrogen to form a fifth reaction mixture comprising alpha-methylbenzyl alcohol; and (f) separating alpha-methylbenzyl alcohol from the fifth reaction mixture and returning the methyl benzyl alcohol to step (a).

First claim

What is claimed is:

1 . A method of preparing propylene oxide comprising:
(a) oxidizing alpha-methylbenzyl alcohol with air to form a first reaction mixture comprising hydrogen peroxide and acetophenone; (b) reacting propylene with the first reaction mixture in the presence of a catalyst to form a second reaction mixture comprising propylene oxide; (c) separating the propylene oxide from the second reaction mixture to form a third reaction mixture; (d) heating the third reaction mixture to decompose hydrogen peroxide, whereby a fourth reaction mixture is formed; (e) hydrogenating the acetophenone in the fourth reaction mixture with hydrogen to form a fifth reaction mixture comprising alpha-methylbenzyl alcohol; and (f) separating alpha-methylbenzyl alcohol from the fifth reaction mixture and returning the methyl benzyl alcohol to step (a).

2 . The method of claim 1 , wherein the molar ratio the alpha-methylbenzyl alcohol to the oxygen of the air of step (a) is from 1:1 to 10:1.

3 . The method of claim 1 , wherein the oxidizing reaction of step (a) is conducted at a temperature from 100° C. to 160° C.

4 . The method of claim 1 , wherein the catalyst is a titanium support on zeolite catalyst.

5 . The method of claim 4 , wherein the titanium support on zeolite catalyst is a TiMWW catalyst or a layered TiMWW catalyst.

6 . The method of claim 1 , wherein the molar ratio of propylene to hydrogen peroxide in step (b) is from 3:1 to 10:1.

7 . The method of claim 1 , wherein step (b) is conducted at a temperature from 20° C. to 150° C. and a pressure from 80 psig to 800 psig.

8 . The method of claim 1 , wherein step (b) further comprises a solvent.

9 . The method of claim 8 , wherein the solvent is alpha-methylbenzyl alcohol and acetophenone or t-butyl alcohol.

10 . The method of claim 1 , wherein step (b) comprises a ratio of alpha-methylbenzyl alcohol to acetophenone to hydrogen peroxide to water from 96:1:2.9:0.1 to 44:44:11.7:0.3.

11 . The method of claim 1 , wherein step (b) further comprises conducting the epoxidation reaction in the presence of a buffer.

12 . The method of claim 11 , wherein the buffer is ammonium acetate, ammonium phosphate, or ammonium dihydrogen phosphate.

13 . The method of claim 1 , wherein the separation of step (c) comprises distilling the propylene oxide from the second reaction mixture.

14 . The method of claim 1 , wherein step (d) is conducted at a temperature from 150° C. to 200° C.

15 . The method of claim 1 , wherein the molar ratio of the acetophenone to hydrogen in step (e) is from 1:4 to 10:1.

16 . The method of claim 1 , wherein step (e) is conducted at a temperature from 60° C. to 100° C. and at a pressure from 250 psig to 500 psig.

17 . The method of claim 1 , wherein the separation of step (f) comprises distilling the alpha-methylbenzyl alcohol from the fifth reaction mixture.

18 . The method of claim 1 , further comprising washing the fifth reaction mixture with a base.

19 . The method of claim 18 , where the base is an aqueous solution of sodium hydroxide or potassium hydroxide with a concentration from 0.1 wt. % to 25 wt. %.

20 . The method of claim 1 , further comprising reacting the fifth reaction mixture after the separation of alpha-methylbenzyl alcohol with hydrogen in the presence of a hydrogenation catalyst forming a sixth reaction mixture and returning at least the methyl benzyl alcohol from the sixth reaction mixture to step (a).

Assignees

• Lyondell Chemical Tech Lp

Inventors

• Dang Vu A
• Leyshon David W
• Nagy Sandor
• Grey Roger A

Classifications

• C07D303/04

  containing only hydrogen and carbon atoms in addition to the ring oxygen atoms · CPC title

• B01J29/7088

  MWW-type, e.g. MCM-22, ERB-1, ITQ-1, PSH-3 or SSZ-25 · CPC title

• C07D301/32

  Separation; Purification · CPC title

• Y02P20/52

  using catalysts, e.g. selective catalysts · CPC title

• C07D301/12 Primary

  with hydrogen peroxide or inorganic peroxides or peracids · CPC title