Patent ID: 8581002
Filing Date: 2013-11-12
Classification: C07C

Abstract:
1. An improved process for working up of a diacetone acrylamide solution obtained by reaction of acetone or diacetone alcohol with acrylonitrile and sulfuric acid and subsequent dilution and neutralization, wherein the process comprises: a) hydrolyzing an organic phase which comprises crude diacetone acrylamide obtained subsequent to the neutralization of the diacetone acrylamide solution by addition of an aqueous alkaline solution in order to remove acrylamide, then subsequently b) after phase separation has been carried out, neutralizing the organic phase which comprises the crude diacetone acrylamide by addition of an acid, then c) in succession, c1) removing, by distillation in the presence of one or more polymerization initiators, low-boiling-point byproducts then c2) removing t-butylacrylamide by distillation carried out at a temperature of from 80 to 150° C. and a pressure of from 0.01 to 20 mbar, and, finally, c3) isolating the diacetone acrylamide by product distillation carried out at a temperature of from 100 to 130° C. and a pressure of from 0.01 to 5 mbar, and d) converting the diacetone acrylamide thus obtained in step c) into a final form.