METHOD FOR PREVENTION OF METALLIC PRECIPITATE REOXICATION/REDISSOLUTION IN AQUEOUS SYSTEM

摘要

A redissolution or reoxidn. of metals pptd. by a chemical reduction in an aqueous complexing or oxidizing soln. is prevented by adding a bicyclic, aromatic and organonitrogen cpd., in a sufficient amt. but insufficient to cause pptn. of the metal, to the aqueous soln. The organonitrogen cpd. is pref. (a) benzotriazole, (b) tolyltriazole, (c) 2-mercaptobenzothiazole, (d) 2-mercaptobenzimidazole, and (e) alkali metal salt of (b), (c) and (d). The metal is pref. Cu, Ni or Co. The process is useful in removing dissolved metals from aq. waste solns.