Platinum and palladium concentrate is obtained from precipitated gold solution reduced by hydrazine hydrate and hydroxylamine hydrochloride. The total content of selenium and tellurium reaches up to 71.15%, and that of gold, platinum and palladium reaches 3.65% in platinum and palladium concentrate. Therefore, the separation of selenium and tellurium from platinum and palladium concentrate is important for the enrichment and recovery of precious metals. Thermodynamic analysis shows that in an alkaline environment, using hydrogen peroxide as oxidant, Se and Te can be oxidized to soluble ionic compounds with a higher valence state, while Au, Pt and Pd stay in the solid phase stably. Oxidative alkaline leaching experimental results show that the suitable conditions for the separation of selenium and tellurium from platinum and palladium concentrate are as follows: the amount of hydrogen peroxide is 250 mL/L, NaOH concentration is 5 mol/L, leaching temperature is 85℃, liquid-solid ratio is 5?1(mL/g) and reaction time is 2 h. Under the suitable conditions, the leaching rates of selenium and tellurium are 82.49% and 92.45%, respectively, while the gold, platinum and palladium are not leached out. The precious metals are enriched, and its total content is 23.18% in oxidative alkaline leaching residue, which is 6.35 times higher than that in the platinum and palladium concentrate.%采用水合肼和盐酸羟胺复合还原沉金后液得到铂钯精矿,其中硒和碲总含量达到71.15%,金、铂和钯总含量达到3.65%,从铂钯精矿中分离硒碲对富集及回收贵金属金铂钯具有重要意义.热力学分析表明:在碱性条件下,采用双氧水作为氧化剂,可以将硒和碲氧化为高价态的离子化合物被浸出,金、铂和钯留在固相中.采用双氧水氧化碱浸分离铂钯精矿中硒碲,实验结果表明其适宜反应条件为:双氧水用量为250 mL/L,NaOH浓度为5 mol/L,反应温度为85℃,液固比为5:1(mL/g),反应时间为2 h,在此适宜条件下,硒和碲的浸出率分别为82.49%和92.45%,金、铂和钯均未被浸出.氧化碱浸后渣中贵金属总含量达到23.18%,相对铂钯精矿富集6.35倍.
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