| 摘要 |
The invention relates to an improvement of a process for preparing N-phosphonomethyl-glycine by oxydation of N-phosphonomethyl-imino-diacetic acid in an aqueous sulphuric acidic medium with hydrogen peroxide. A characteristic feature is using a waste acid liquor as reaction medium formed as aqueous sulphuric acid and obtained after the separation of N-phosphonomethyl-glycine when carrying out oxydation. This solution is optionally diluted with water until a concentration of 12-18 weight % of sulphuric acid and 3-5 weight % of N-phosphonomethyl-glycine. |
