PRODUCTION OF PROPYLENE GLYCOL MONOALKYL ETHER

Processes for producing propylene glycol monoalkyl ether are described herein and include contacting propylene oxide and an alcohol in the presence of an alkali or alkaline earth metal alkoxide catalyst to produce an alkoxylation mixture including propylene glycol monoalkyl ether; distilling the alkoxylation mixture to produce a first overhead stream including propylene oxide and the alcohol and a first bottoms stream including propylene glycol monoalkyl ether; distilling the first bottoms stream to produce a second overhead stream including purified propylene glycol monoalkyl ether and a second bottoms stream including heavier byproducts; further distilling the second bottoms stream to form a resulting bottoms stream including caustic and heavier byproducts; introducing an alkali metal borohydride into at least a portion of the resulting bottoms stream to form an alkali metal borohydride containing stream; and introducing the alkali metal borohydride containing stream into one or more distillations upstream of recovery of the second overhead stream.