Method for extracting osmium, iridium and ruthenium to be directly processed into corresponding compounds

Abstract

The invention relates to a method for extracting osmium, iridium and ruthenium to be directly processed into corresponding compounds. After aluminum is molten, a material is added, heating is conducted, a molten alloy is obtained, and the molten alloy is subjected to water-quenching into alloy particles; the alloy particles are added into alkali liquor, aluminum is dissolved in the alkali liquor, the alloy is mixed with sodium peroxide and sodium hydroxide, heating is conducted, and a melt is obtained; the melt is placed in water, a mixture of a melt containing iridium and a solution containing ruthenium and osmium is obtained, a sodium hydroxide solution is added, chlorine is led in, ruthenium and osmium are distilled to enter into a gas phase and then are led into a hydrochloric acid solution containing ethyl alcohol, and through baking and crystallizing, ruthenium trichloride is obtained; then ruthenium trichloride is led into a mixed solution containing ethyl alcohol and sodium hydroxide, potassium hydroxide and ethyl alcohol are added, amaranth sediment is obtained, drying is conducted, and potassium osmate is obtained; and distilled residual liquid is subjected to solid-liquid separation, a solid body containing iridium is obtained, the solid body containing iridium is dissolved through aqua regia, Na2S, hydrogen peroxide for oxidation and ammonium chloride are added, drying is conducted, and ammonium chloroiride is obtained. The activity is lowered, the safety and reliability are achieved, the yield rate is high, and pollution discharging is avoided.

Description

technical field [0001] The invention relates to a method for extracting precious metals osmium, iridium and ruthenium, in particular to a method for extracting precious metals osmium, iridium and ruthenium from insoluble materials and directly processing them into corresponding compounds. The invention belongs to the technical field of precious metal extraction. Background technique [0002] When extracting precious metals such as osmium, iridium, and ruthenium from refractory minerals, the existing technology is: 1) First, it needs to be crushed, that is, use zinc, aluminum or zinc-aluminum alloy to form an alloy with the material at high temperature; 2) Then Then use hydrochloric acid or sulfuric acid to dissolve zinc or aluminum to obtain osmium, iridium, ruthenium and other precious metal powders; 3) Then use the following two methods to separate and extract osmium, iridium, ruthenium and other precious metals: one is wet distillation of osmium and ruthenium; The other ...

AI Technical Summary

Problems solved by technology

[0004] When using zinc for shredding, zinc is severely oxidized at high temperature, resulting in incomplete shredding of materials, and a large amount of zinc oxidation causes serious loss of materials and increased costs; when using aluminum for shredding, not only does it consume a lot of acid to dissolve aluminum, but Moreover, the solid-liquid separation after dissolution is more difficult;

[0005] When using zinc-aluminum alloys for crushing, although the defects of serious zinc loss, large acid consumption, and difficult solid-liquid separation that exist in zinc and aluminum crushing alone are partially overcome, the above-mentioned defects of the two cannot be completely overcome.

[0006] 2. Defects in acid leaching process

[0007] Regardless of using a single zinc, aluminum or zinc-aluminum alloy to crush the material, the obtained alloy has the following disadvantages in the acid leaching process: 1) The dissolution rate of acid is slow and the efficiency is too low; 2) The consumption of acid is extremely large; 3) It is difficult to completely separate the solid and liquid after acid dissolution; 4) The solid slag after acid leaching is acidic, and a large amount of water and time are needed to wash the acidic solid slag to neutrality, which will inevitably generate a large amount of waste water, increase the cost of waste water treatment, and further Seriously, the aqua regia insoluble materials containing osmium, iridium, platinum, after leaching in acidic system, active precious metal powders such as osmium, iridium, platinum, are easily oxidized, and even explosion accidents occur.

[0008] 3. Defects of traditional wet distillation and fire distillation

[0009] Traditional wet distillation needs to consume a large amount of expensive sodium bromate or sodium chlorate; the biggest defect of fire distillation is that the highly oxidizable precious metal powder has high activity, which is prone to explosion and cause safety accidents; It is slow, the reaction time is long, and the oxidation and volatilization are not complete. It is necessary to neutralize and precipitate osmium dioxide with sulfuric acid after water immersion. The process is complicated and the efficiency is low.