Abstract: A process is provided for removing soluble metallic salts, such as calcium, copper, zinc, magnesium, tin, iron, or mixtures thereof, from a phosphate ester functional fluid. The process comprises contacting the functional fluid with an effective amount of a chelating agent capable of precipitating at least part of the metallic salts contained therein to form a precipitate, and subsequently separating the precipitate from the functional fluid. A preferred chelating agent is ethylenediaminetetraacetic acid, its alkali metal, alkaline earth or ammonium salts. The process is particularly useful in the reclamation of used triaryl phosphate esters, particularly tertbutylphenyl phenyl phosphates, containing the aforementioned soluble metallic salts.