Process for purification of polyether carbonate polyols

摘要

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.

主权项

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.