Process for purification of polyether carbonate polyols

Patent metadata

Field	Value
Publication number	US-9527958-B2
Application number	US-201414268307-A
Country	US
Kind code	B2
Filing date	May 2, 2014
Priority date	May 2, 2014
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

This invention relates to a process for the production of a high purity polyether carbonate polyol. The high purity polyether carbonate polyols prepared by the process herein contain a low level of catalyst residues. The process adds diatomaceous earth to a polyether carbonate polyol to form a suspension, mixes the suspension for a specified time period at a specified temperature, and filters the suspension to form the high purity polyether carbonate polyol.

First claim

What is claimed is:

1. A process for producing a high purity polyether carbonate polyol which contains no more than 90 ppm of catalyst residue, consisting of
(1) adding from 0.5% to 5% by weight, based on 100% by weight of polyether carbonate polyol, of diatomaceous earth having a permeability rating of less than or equal to 0.200 darcys to a polyether carbonate polyol to form a suspension;
(2) mixing the suspension, formed in (1) for a time period of from 30 minutes to 5 hours at temperature in the range of from 20° C. to 150° C.;

and
(3) filtering the suspension from (2), thereby forming the high purity polyether carbonate polyol.

2. The process of claim 1 , which comprises (1) adding from 0.75% to 2.0% by weight, based on 100% by weight of polyether carbonate polyol, of diatomaceous earth to the polyether carbonate polyol.

3. The process of claim 1 , which comprises (1) adding from 1.00 to 1.75% by weight, based on 100% by weight of polyether carbonate polyol, of diatomaceous earth to the polyether carbonate polyol.

4. The process of claim 1 , wherein said diatomaceous earth has a permeability rating of from 0.01 to 0.200 darcys.

5. The process of claim 1 , wherein said diatomaceous earth has a permeability rating of from 0.02 to 0.150 darcys.

6. The process of claim 1 , which comprises (2) mixing said suspension formed in (1) for a time period of from 60 minutes to 240 minutes.

7. The process of claim 1 , which comprises (2) mixing said suspension formed in (1) for a time period of from 60 to 90 minutes.

8. The process of claim 1 , which comprises (2) mixing said suspension formed in (1) at a temperature in the range of from 70 to 125° C.

9. The process of claim 1 , which comprises (2) mixing said suspension formed in (1) at a temperature in the range of from 75 to 120° C.

10. The process of claim wherein said diatomaceous earth is selected from the group consisting of non-calcined diatomaceous earth, calcined diatomaceous earth, flux calcined diatomaceous earth and acid washed diatomaceous earth.

11. The process of claim 1 , wherein said polyether carbonate polyol is prepared with a double metal cyanide catalyst.

12. The process of claim 1 , wherein said high purity polyether carbonate polyol contains no more than 9 ppm of cobalt residue.

Assignees

• Bayer Materialscience Llc
• Covestro Llc

Inventors

• Uthe Peter
• Bailey Stephen
• Gastinger Robert

Classifications

• C08G64/34

  and cyclic ethers · CPC title

• C08G64/302

  and cyclic ethers · CPC title

• C08G64/0208

  saturated · CPC title

• C08G64/406 Primary

  Purifying; Drying · CPC title