Process for the preparation of alkylphosphates

Preparing completely water-soluble tetraalkyl-bisphosphate, comprises (a) reacting a tetrachloro-bisphosphate with at least one alcohol, (b) when in step (a) at least 50% of the phosphate-chloride groups contained in the tetrachloro-bisphosphate are reacted, reacting the reaction mixture from step (a) with a base containing at least one substance, (c) then adding sufficient water to the reaction mixture from step (b) to form a mixture consisting of two separate liquid phases and (d) separating the tetraalkyl-bisphosphate containing phase from the mixture obtained in the step (c). Preparing completely water-soluble tetraalkyl-bisphosphates, comprises (a) reacting a tetrachloro-bisphosphate with at least one alcohol, (b) when in step (a) at least 50% of the phosphate-chloride groups contained in the tetrachloro-bisphosphate are reacted, reacting the reaction mixture from step (a) with a base containing at least one substance of formula (cation(n+)) a(X(m-)) b, (c) then adding sufficient water to the reaction mixture from step (b) to form a mixture consisting of two separate liquid phases and (d) separating the tetraalkyl-bisphosphate containing phase from the mixture obtained in the step (c). cation(n+) : a cation of charge n; X(m-) : an anion of charge m; and a, b : integers, which satisfy the relationship nx a is equal to mx b. Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung von Tetraalkylbisphosphaten durch Umsetzung von Tetrachlorbisphosphaten mit Alkoholen, Neutralisation des gebildeten Chlorwasserstoffs mit einer Base und Abtrennung des bei der Neutralisation gebildeten Salzes von der Reaktionsmischung als konzentrierte wässrige Lösung.