PURPOSE: To easily recover cobalt carbonate at a low cost and to obtain a high-grade copper refining material by removing zinc from the clarified residue obtained from a zinc refining stage, then removing copper from the obtained acid-cleaned residue, adding H2S to the soln. to remove As, Cd, and Cu, adding soda ash to the cleaned soln., and filtering the precipitate.
CONSTITUTION: Water and sulfuric acid are added to the clarified residue produced from the clarifying stage of zinc refining and contg. Cu, Zn, Cd, and As as the essential components in addition to Co to control the pH to 2W4, the liq. is agitated and cleaned with an acid, the precipitate is filtered and washed with water to elute the greater part of Cd, and the obtained acid-cleaned soln. is separated to obtain the acid-cleaned residue. Water and sulfuric acid are added to the residue to control the pH to 2W3, the soln. is heated to 50W60°C, air is blown in to selectively dissolve Co, the precipitate is filtered and washed to separate a copper-contg. residue, and a soln. contg. Co, etc., is obtained. Na2S and sulfuric acid are then added to the soln. and heated to about 60°C to precipitate AsS, CdS, and CuS by the generated H2S, the precipitated sulfides are separated and removed, sulfuric acid is added to the filtrate to control the pH to ≤3, hence the filtrate is clarified, soda ash is added to the clarified filtrate at 60W80°C to adjust the pH to 6W9, and the obtained precipitate is filtered and washed with water.
SEKIYA TETSUO
MATSUKURA DAISAKU
FURUTA MOTOMI
Next Patent: METHOD FOR CHANGING GLASS TEMPERATURE IN FORE HEARTH AT CHANGE OF PRODUCT