APPARATUS FOR RECOVERING NOBLE METAL COMPOUND

摘要

PURPOSE:To recover only the noble metal compd. at a high concn. by separating the noble metal compd. in a treating liquid with a reverse osmosis apparatus and concentrating the liquid permeated therethrough with an electrodialysis apparatus utilizing both anion and cation exchange membranes. CONSTITUTION:The treating liquid of plating contg. the noble metal compd. is separated by the reverse osmosis apparatus 6 utilizing a reverse osmosis membrane 6a consisting of cellulose acetate. The liquid 3a permeated therethrough is then concentrated in the electrodialysis apparatus 9 provided with diluting chambers 10 and concentrating chambers 11 formed by alternate partition with the anion exchange membranes A and the cation exchange membranes K. The concd. liquid 13 is returned by a pump 21 to a plating cell 1 where the liquid is used to prepare the plating liquid. The liquid 13 is further dried by a dryer 22 and the noble metal compd. is recovered in the form of crystal or powder. Only the noble metal compd. is recovered at the high concn. and the cost is reduced by the above-mentioned apparatus.