TREATMENT OF CHEMICAL PLATING WASTE LIQUID

摘要

PURPOSE:To separate and recover an available component from a waste liquid and to contriveits reutilization by removing a metalic material from a chemical plating waste liquid and thereafter adding alkaline earth metallic salt and precipitating an organic acid component contained in the waste liquid as insoluble salt. CONSTITUTION:The metallic materials contained in a chemical plating waste liquid are removed by using a suitable metal remover. An organic acid component contained in the waste liquid is precipitated as insoluble alkaline earth metallic salt by adding alkaline earth metallic salt such as CaCl2 to the waste liquid wherein a metallic material is removed. This precipitate is separated and recovered. Or furthermore the precipitate is redissolved by adding sulfuric acid to the separated precipitate and organic acid is produced and also the precipitate of alkaline earth metallic sulfate is formed. An organic acid soln. is recovered by separating this precipitate and this organic acid is reused as a component of a chemical plating liquid. The environmental pollution properties of the waste liquid can be decreased by this treatment.