Methods for producing epoxidation catalysts and epoxidation methods utilizing them

Patent metadata

Field	Value
Publication number	US-9259726-B2
Application number	US-201214114717-A
Country	US
Kind code	B2
Filing date	May 25, 2012
Priority date	Jun 6, 2011
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

A method for producing epoxidation catalysts is provided. The catalyst comprises a support, a catalytic species, maganese and at least one alkali metal and/or promoter. The catalytic species may be silver. The catalyst is prepared by a method wherein at least a portion of the manganese is impregnated in a step separate from the at least one alkali metal and/or promoter. Advantageously, catalysts produced by the present method may exhibit greater efficiencies than catalysts produced by conventional methods. A method for the epoxidation of alkylenes using the catalysts so produced is provided as is a method for using the alkylene oxides for the production of 1,2-diols, 1,2-carbonates, 1,2-diol ethers, or alka-nolamines.

First claim

We claim:

1. A method for making an epoxidation catalyst comprising a support, silver, manganese and greater than 35 ppm sodium, comprising:
Impregnating the support with manganese prior to impregnating the support with sodium;
Impregnating the support with silver prior to, at the same time as or after impregnation with manganese.

2. The method of claim 1 , wherein the manganese is impregnated into the support at the same time as at least a portion of the silver.

3. The method of claim 1 , wherein the catalyst further comprises at least one alkali metal and/or promoter in addition to sodium and manganese.

4. The method of claim 3 , wherein the at least one additional alkali metal and/or promoter comprises rhenium, cesium, lithium, sulfate or combinations of these.

5. The method of claim 1 , wherein the manganese comprises Mn-EDTA complex.

6. The method of claim 4 , wherein the at least one additional alkali metal and/or promoter comprises rhenium.

7. The method of claim 1 , wherein the catalyst is exposed to an elevated temperature not exceeding 600° C. between impregnating the support with manganese and impregnating the support with sodium.

8. The method of claim 7 , wherein the elevated temperature does not exceed 400° C.

9. The method of claim 4 , wherein the manganese and at least a portion of the silver are deposited in a first impregnation and the sodium, cesium, lithium, rhenium, sulfate and a second portion of silver are deposited in a second impregnation.

10. A method for making an epoxidation catalyst comprising a support, silver, manganese and greater than 35 ppm sodium, comprising:
Impregnating the support with manganese separately from sodium and exposing the catalyst in between impregnations to an elevated temperature not exceeding 600° C.

11. The method of claim 10 , wherein the elevated temperature does not exceed 400° C.

12. The method of claim 10 , wherein the sodium is impregnated into the support at the same time as at least a portion of the silver prior to the impregnation of manganese.

13. The method of claim 12 , wherein the sodium and silver are impregnated into the support at the same time as at least one other alkali metal and/or promoter.

14. The method of claim 10 or 13 , wherein the manganese and at least a portion of the silver are impregnated into the support at the same time as at least one other alkali metal and/or promoter.

15. The method of claim 14 , wherein the at least one other alkali metal and/or promoter comprises cesium, rhenium, sulfate or combinations of these.

Assignees

• Gopal Srikant
• Murthy Lakshmi N Vutukuru
• Basrur Arun G
• Dow Technology Investments Llc

Inventors

• Gopal Srikant
• Murthy Lakshmi N Vutukuru
• Basrur Arun G

Classifications

• B01J2523/15

  Caesium · CPC title

• B01J27/055

  with alkali metals, copper, gold or silver · CPC title

• B01J2523/11

  Lithium · CPC title

• B01J2523/18

  Silver · CPC title

• C07D301/10

  with catalysts containing silver or gold · CPC title