Patent ID: 7071354
Filing Date: 2006-07-04
Classification: C07F

Abstract:
1. A process for the recovery of N-phosphonomethylglycine from an aqueous mixture which contains N-phosphonomethylglycine, ammonium halides, and alkali metal or alkaline earth metal halides and optionally organic impurities in dissolved form, where (a) the pH of the mixture is adjusted to a value in the range from 2 to 8, (b) a separation of the mixture on a selective nanofiltration membrane is performed, a retentate which is richer in N-phosphonomethylglycine and poorer in halides and a permeate which is richer in halides and poorer in N-phosphonomethylglycine being obtained, and (c) the N-phosphonomethylglycine is recovered from the retentate.