摘要
technology for recovering silver and palladium from multilayer ceramic capacitors (MLCC) scraps was studied. 91% silver and 98% palladium are respectively leached from scraps (200 mesh) under the conditions of 4 mol/L HNO_3, 80℃, 2 h (s/l=1∶3). Silver can be precipitated with hydrochloric acid from leaching solutions. Purity of coarse silver bullion obtained from melting silver chloride is 98%. Silver recovery is 88%. Palladium can be reduced and precipitated respectively from silver raffinate and leaching residue scrub solutions by iron powders and butyl xanthate. Purity of palladium is 99.95% by traditional refining method. Palladium recovery is 95%.
technology for recovering silver and palladium from multilayer ceramic capacitors (MLCC) scraps was studied. 91% silver and 98% palladium are respectively leached from scraps (200 mesh) under the conditions of 4 mol/L HNO_3, 80℃, 2 h (s/l=1∶3). Silver can be precipitated with hydrochloric acid from leaching solutions. Purity of coarse silver bullion obtained from melting silver chloride is 98%. Silver recovery is 88%. Palladium can be reduced and precipitated respectively from silver raffinate and leaching residue scrub solutions by iron powders and butyl xanthate. Purity of palladium is 99.95% by traditional refining method. Palladium recovery is 95%.