Glufosinate-ammonium separating and purifying method

The invention discloses a glufosinate-ammonium separating and purifying method. The method includes the steps of conducting ammoniation on a glufosinate-ammonium acidolysis solution or solid glufosinate-ammonium hydrochloride, conducting drying to obtain a glufosinate-ammonium crude product A, adding the glufosinate-ammonium crude product A to alcohol, conducting filtering to obtain a glufosinate-ammonium crude product B, adding the glufosinate-ammonium crude product B to phosphate ester, conducting filtering to obtain filtrate, washing a filter cake through phosphate ester, combining filtrate with washing liquid to obtain a glufosinate-ammonium crude product C, adding the glufosinate-ammonium crude product C to water to be extracted, and taking a water layer which can be directly used as a glufosinate-ammonium aqueous solution or obtaining high-purity glufosinate-ammonium active compounds after the water layer is spray-dried. The method is simple in step, the content of chloride impurities in the obtained glufosinate-ammonium aqueous solution or glufosinate-ammonium active compounds is extremely low, basically no organic impurities exist, the purity of the separated glufosinate-ammonium active compounds can reach 98% or higher, and the recovery rate of glufosinate-ammonium reaches up to 98% or higher. Compared with the traditional process, the method has the higher advantages of cost, safety, environmental friendliness and quality and has extremely-high social value and economic value.