Removal of copper and cyanide from solution using activated carbon

The removal of copper and cyanide from aqueous solution by activated carbon has been investigated. Using a coal-based activated carbon, initial concentrations of 244 to 2441 mg/litre total cyanide combined with 61 to 610 mg/litre copper were reduced to a minimum of 3.6 mg/litre total cyanide and 0.6 mg/litre copper in the presence of a fixed initial quantity of air.Cyanide removal was, found to be augmented by the presence of copper in solution, and by the supply of additional air.It is suggested that cyanide removal is accomplished by catalytic oxidation on the carbon surfaces, and that additional cyanide is removed in the presence of copper by adsorption of cyano-cuprate complexes onto the activated carbon.