Preparation method of high-purity platinum powder

Abstract

The invention relates to a preparation method of high-purity platinum powder. The method comprises the steps that Step 1, sponge platinum is added into a dissolving agent for dissolving to obtain a chloroplatinic acid solution; Step 2, ammonium chloride is added into the chloroplatinic acid solution obtained in the step 1 to precipitate ammonium chloroplatinate; Step 3, the ammonium chloroplatinate precipitation liquid is poured into a nanofiltration membrane, impurity ions are removed to obtain impurities and platinum-containing permeate liquid, and the impurities are treated as a stock solution and are returned for filtering and impurity removal again; Step 4, a reducing agent is added into the platinum permeation liquid for deep reduction, and platinum is reduced to be in a powder form; the obtained platinum powder is boiled and washed with nitric acid and hydrofluoric acid and then is fully washed with deionized water, and the high-purity platinum powder is obtained after vacuum drying. The waste liquid and the impurities are repeatedly filtered and washed, so that waste of resources can be reduced, and meanwhile, the environmental pollution is also reduced; through repeatedly washing and filtering of the stock solution, the purity of the platinum powder can be further improved.

Description

technical field [0001] The invention relates to the technical field of preparation of platinum powder, in particular to a preparation method of high-purity platinum powder. Background technique [0002] High-purity platinum has good chemical stability, high electrical conductivity and thermal conductivity, and unique electrical, magnetic, optical and other properties. It is widely used in national defense, military industry, satellite, electronics and other industries. High-purity platinum powder has become a guarantee for the performance of semiconductor devices. It is an indispensable and irreplaceable material for the development of semiconductor technology. With the development of semiconductor technology and radio precision technology, the purity requirements of platinum metal are getting higher and higher. Because the properties of the metal tend to be masked by impurities when the metal fails to reach a certain purity, the presence of trace impurities or even ultra-t...

AI Technical Summary

Problems solved by technology

At present, the preparation method of high-purity platinum in China is mainly based on repeated precipitation of ammonium chloroplatinate. The purity of platinum prepared by this method is low, which cannot meet the requirements of modern scientific development.

The production of high-purity platinum in foreign countries mostly uses physical metallurgical methods, such as pulling single crystals. After discharge, the small amount of crude platinum contained in the waste liquid and impurities will be wasted, and it will also cause environmental pollution.