POLYETHER-POLYOL PRODUCTION PROCESS Russian patent published in 2005 - IPC

FIELD: industrial organic synthesis.

SUBSTANCE: process of producing polyether-polyols containing at most 15 ppm sodium or potassium comprises following steps: (a)interaction of initiator having at least to active hydrogen atoms with at least one alkylene oxide in presence of catalyst containing alkali metal hydroxide to form polyether-polyol reaction product; (b) neutralization of polyether-polyol reaction product obtained in step (a) by bringing it into contact with acid having pKa below 5 and water, said acid and said water being introduced in such an amounts that finally content of water is 1 wt % or of the total weight of polyether-polyol present, while molar ratio of acid to alkali metal hydroxide ranges from 0.3:1 to 1.0:1; optionally (c) reduction of content of water in reaction mixture to 0.5 wt % or less of the total weight of polyether-polyol; and (d) removal of salt crystals from polyether-polyol and recovery of neutralized polyether-polyol containing not more than 15 ppm sodium and/or potassium. In the course of neutralization, magnesium silicate or aluminum silicate is added in amount below 0.05 wt parts per 100 wt parts of polyether-polyol and also hydrated inorganic acid metal salt in amount 0.01% of the weight of polyether-polyol.

EFFECT: minimized consumption of heat during neutralization step and reduced neutralization time.

7 cl, 6 ex