Method for purifying N-methyl-2-pyrrolidone

摘要

A method for purifying N-methyl-2-pyrrolidone is disclosed. The method comprises treating N-methyl-2-pyrrolidone with an alumina that desorbs less than 100 mumol/g of isobutylene between 225° C. and 400° C. in a standard tert-butyl alcohol dehydration test. The method enables the removal of at least about 80% of amine impurities or at least about 60% of APHA color from the NMP at 4 bed volumes treated.