automobile bumpers with nickel and chromium for corrosion resistance electroplating aircraft engine parts with cadmium to allow disassembly after high temperature service several of these metal finishing processes involve electroplating which is a process for depositing a metal film on a surface by chemical or electrochemical reduction of salts of these metals in solution at the surface to be coated specific examples of electroplating are coating zinc castings with a brass film by electro reduction of a mixture of copper and zinc cyanide salts and coating steel with a nickel film by electro reduction of nickel salts waste waters from all of these processes contain dissolved heavy metal salts as well as the possibility of other materials in forms such that it is not advantageous to utilize or sell these waters without further treatment the invention being described is a process for treating these waste waters to detoxify them for discharge it is also a process for recovery of metal values from these waste waters it is also a process for recovery of metal values from these waste waters in salable form the waste water is introduced to a portable cannister filled with a bed of ion exchange resin a portable cannister is shown in fig1 a the body of the cannister 1 consists of a cylinder 13 34 in.