Patent ID: 9745236
Date: 2017-08-29
CPC Classifications: B01D,C07C

Claim:
1. Distillative process for obtaining ditrimethylolpropane from solutions comprising ditrimethylolpropane, consisting of: (a) separating the solution comprising ditrimethylolpropane in a first distillation unit into a first tops fraction comprising low-boiling compounds having a lower boiling point than ditrimethylolpropane and a bottoms fraction; (b) introducing the bottoms fraction as obtained after step a) into a second distillation unit having at least 5 theoretical plates, said unit being configured as a thin-film evaporator with a column attachment, and drawing off a second tops fraction comprising intermediate-boiling compounds having a lower boiling point than ditrimethylolpropane, and withdrawing a bottoms fraction; and (c) introducing the bottoms fraction as obtained after step b) into a third distillation unit having at least 4 theoretical plates, said unit being configured as a thin-film evaporator with a column, attachment, in which ditrimethylolpropane is obtained as a third tops fraction and high boilers are removed as a bottoms fraction.