| In this work, a new hydrometallurgical method of treating with theantimony-gold alloy by high-pressure oxidation leaching has beeninvestigated, in which, copper and nickel can be firstly removed from thealloy, which let the follow-up treatment be simple.The exploration indicated that, the concentration of chloride ions,acidity, leaching potential and the dropping speed of H2O2 would be thekey influences on base-noble separation. It is contradictory and mutualrestraint between the insolubility of silver and the complete removal ofbase metals, and it is difficult to find a balance between them. To ensurethe complete dissolution of base metals needs higher leaching potential,higher concentration of chloride ions and higher acidity, this time, silverinevitably enter the solution, all influences will change while thecomponent changes, therefore, it is not easy to get the depth-separationpurpose by controlling leaching potential in the chloride solution.The process includes two main steps, the high-pressure oxidationleaching process and the hydrochloric acid leaching process. The residuesremoved copper and nickel in the high-pressure oxidation leachingprocess are gonging to remove antimony and lead in the hydrochloric acidleaching process, as a result, a high grade crude gold is obtained. Underthe fixed conditions of the hydrochloric acid leaching process, the effectsof the concentration of sulfuric acid, the liquid-solid ratio, theconsumption of hydrogen peroxide, leaching time and leachingtemperature on the indexes of the process have been investigated. Underthe optimal conditions: [H2SO4]=1.5mol/L, L:S=7:1, the amount ofhydrogen peroxide 1.2 times the theoretical amount, leaching time 4h,leaching temperature 427K, and the leaching efficiencies of copper andnickel are over 99ï¼…, the leaching efficiencies of antimony is 92.8ï¼…, thegrade of the crude gold reach up to 66.1ï¼…, which has reached a satisfiedpurpose of removal base metals.
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