Patent ID: 8987523
Filing Date: 2015-03-24
Classification: C07C

Abstract:
1. Process for obtaining ditrimethylolpropane and trimethylolpropane-enriched product streams from the high-boiling fractions and residues which are obtained in the distillative purification of trimethylolpropane, characterized in that: (a) these high-boiling fractions and residues are combined and water is added to produce an aqueous solution; (b) the aqueous solution produced according to step a) is treated at a temperature of 160 to 280° C. and at a pressure of 1 to 30 MPa with hydrogen in the presence of a catalyst and of an acidic compound; (c) the aqueous solution obtained according to step b) is removed from the catalyst and further solids, if present; (d) the aqueous solution obtained according to step c) is treated both with basic and with acidic ion exchangers; (e) water and low boilers present are removed from the aqueous eluate obtained according to step d); and (f) a trimethylolpropane-enriched product stream is distilled out of the residue obtained after step e) at elevated temperature and reduced pressure, leaving ditrimethylolpropane as the distillation residue.