13. Sources of industrial silver pollution

13.1 Silvering and de-silvering waste (mirrors, electroplating, etc.)

These include silver electrolyte baths, desilvering solutions from the electronics and crafts sectors, and mirror silvering solutions. Reformed cyanide baths and electroplating rinse water must be decyanidized. They must not exceed 0.1 mg/L CN ^– when discharged. Cyanide is destroyed with sodium hypochlorite. Silver is recovered by electrolysis or fixed by resins. A special case is ammoniacal silver solutions used with a reducing agent for silvering mirrors....