The invention relates to a silver
anode mud treatment process. The process is characterized by leaching silver
anode mud with
nitric acid, wherein silver,
palladium and base metals enter into solution while gold and
platinum remain in residue; after
roasting the leaching residue and removing impurities, using a cast gold
anode plate to electrolyze the leaching residue to obtain gold No. 1 and using
electrolyte for recycling
platinum; regulating the pH value of
leachate and adding mixed precipitator A solution to selectively precipitate
palladium to obtain
palladium precipitate residues; solution after palladium
precipitation mainly being AgNO3 solution and returning the AgNO3 solution to undergo silver
electrolysis; dissolving the palladium precipitate residues with
aqua regia and filtering the dissolved solution to obtain the filter residue which is mainly AgCl, reducing the filter residue with hydrazine
hydrate to obtain crude silver
powder and returning the crude silver
powder to a cast silver anode plate; and concentrating and carrying out
ammonium on the solution after
dissolution to obtain (NH4)2PdCl6 precipitate, dissolving the (NH4)2PdCl6 precipitate with
ammonia and acidizing the (NH4)2PdCl6 precipitate with
hydrochloric acid to obtain Pd(NH3)2Cl2 precipitate, then reducing the Pd(NH3)2Cl2 precipitate with hydrazine
hydrate and then
drying the reduction product to obtain spongy palladium, wherein the produced filtrate is returned to the concentration process. The invention has the advantages of less
precious metal loss, low cost, strong practicability, high comprehensive recoverability and obvious economic benefit.