Method for preparing platinum powder with large specific gravity from crude platinum

Abstract

The invention discloses a method for preparing large-specific-gravity platinum powder from crude platinum, and belongs to the technical field of platinum group metal refining. According to the method, efficient purification of platinum and preparation of large-specific-gravity platinum powder are realized by adopting a combined precipitation method through the core steps of dissolving for liquid preparation, ammonium chloride precipitation, dissolving for impurity removal, acidification precipitation, reduction and the like. The method comprises the following specific steps: dissolving crude platinum with aqua regia to prepare a crude platinum solution, precipitating with ammonium chloride to generate ammonium chloroplatinate, dissolving with a special reagent to remove platinum group metal and base metal impurities, acidifying, precipitating, further purifying, and finally reducing with a liquid phase to obtain the large-specific-gravity platinum powder. The method is short in technological process, easy in process control, simple in operation equipment and suitable for large-scale production, the product purity is higher than 99.99% of sponge platinum requirements in the national standard GB / T-1419, the tap density is larger than 3.5 g / mL, and the method has wide application value in multiple fields of jewelry, chemical engineering, medicine, electronics, ceramics and the like.

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