PURIFICATION OF BIDENT ORGANOPHOSPHORUS EXTRACTION PRODUCTS

摘要

The subject of the invention is a process for the purification of a compound of general formula: ## STR3 ## in which R 1 and R 2 are each independently selected from C 1 -alkyl groups at C8, R3 and R4 are R or RO, where each R is independently selected from C1 to C15 alkyl, aryl, arylalkyl and alkylaryl, and X is halogen, characterized in that it comprises distilling said compound in a thin-film evaporator. / P