Rejuvenated catalytic oxidation of waste water, particularly for removal of cyanide and sulfur compounds

A method for treating waste water comprising:

• (a) directing a source of oxygen and a waste water containing at least one offensive substance selected from the group consisting of cyanide, sulfide, sulfite, thiosulfate, mercaptan, disulfide, ammonia and mixtures thereof, upwardly through a catalyst comprising an activated carbon having an amount of copper thereon that is catalytically active to catalyze the oxidation of the offensive substance in a reaction zone under conditions effective to reduce the concentration of the offensive substance contained in the waste water and to thereby produce a treated waste water, said conditions comprising a temperature of from about 120.degree. F. to about 250.degree. F. and a pH of from about 8 to about 10, the catalytically active amount of copper comprising less than about 800 ppm copper on the activated carbon;
• (b) adding sufficient soluble copper to the waste water prior to directing it into the reaction zone to maintain the catalytically active amount of copper on the activated carbon and to maintain a concentration of copper in the treated waste water at a level between about 1 ppm and about 0.001 ppm;
• and
• (c) discharging the treated waste water from the reaction zone.

A method for treating waste water comprising:

• (a) directing a source of oxygen and a waste water containing at least one offensive substance selected from the group consisting of cyanide, sulfide, sulfite, thiosulfate, mercaptan, disulfide, ammonia and mixtures thereof, over a catalyst comprising an activated carbon having an amount of copper thereon that is catalytically active to catalyze the oxidation of the offensive substance in a reaction zone under conditions effective to reduce the concentration of the offensive substance contained in the waste water and to thereby produce a treated waste water, said conditions comprising a temperature of from about 100.degree. F. to about 400.degree. F. and a pH of from about 6 to about 12, the catalytically active amount of copper on the activated carbon comprising less than about 1000 ppm;
• (b) adding sufficient soluble copper to the waste water prior to directing it into the reaction zone to maintain the catalytically active amount of copper on the activated carbon and to maintain a concentration of copper in the treated waste water at a level between about 3 ppm and about 0.001 ppm;
• and
• (c) discharging the treated waste water from the reaction zone.