Process of producing polyglycerol from crude glycerol

摘要

The present invention relates to a process for accelerated preparation of polyglycerol from crude glycerol using microwave irradiation as the heat element in the presence of soap as the catalyst. The process includes the steps of (a) heating the crude glycerol that contain soap to an elevated temperature for a certain reaction time by using a microwave technology, (b) acidifying the crude polyglycerol with mineral acid at a specific temperature and centrifuging acidified crude product obtained from step (b) at a specific temperature for a certain duration of time.

主权项

1. A process for preparing polyglycerol from crude glycerol, the process including the steps of:
(a) heating the crude glycerol that contains about 60 to 90% glycerol and 10 to 15% by weight soap that is a salt of a fatty acid having from 8 to 22 carbon atoms to an elevated temperature from about 250° C. to about 270° C. for a reaction time from about 20 minutes to about 30 minutes by using a microwave technology, such that 95 to 100% of the crude glycerol is converted to linear polyglycerol(s) with no cyclic polyglycerol formation; (b) acidifying the crude polyglycerol product with mineral acid to hydrolyze the soap to yield a fatty acid and a salt of the mineral acid; and (c) centrifuging acidified crude product obtained from step (b) at 60-80° C. , a centrifugal force of the centrifuging separating (1) the fatty acid and (2) the salt of the mineral acid from (3) the polyglycerol product, the acidified crude product separating into three layers including a layer of the fatty acid, a layer of the purified polyglycerol, and a layer of the salt of the mineral acid after centrifuging.