Method for recycling and utilizing precious metal in IrOsRu ore

Abstract

The invention discloses a method for recycling and utilizing a precious metal in an IrOsRu ore, which comprises the following process steps: 1) blending and shredding raw materials: mixing and shredding IrOsRu ore, zinc and aluminum to form raw materials; 2) performing acid leaching to remove zinc and aluminum; 3) performing alkali dissolution and water leaching: melting the filter residue with asolid base, and performing water leaching; 4) performing oxidative distillation to remove cesium: adding nitric acid to produce and absorb osmium tetroxide vapor; 5) performing recovery of ruthenium:adding sodium chlorate to produce and recycle osmium tetroxide vapor, performing concentration and crystallization by rotary evaporation to obtain ruthenium trichloride; and 6) performing purificationof hydrazine, concentration of filtrate, etc., to obtain ammonium chloroiridate precipitation, and then filtering and drying the precipitation. According to the method for recycling and utilizing precious metal in IrOsRu ore, the IrOsRu ore, zinc and aluminum are shredded at high temperature in an intermediate frequency furnace to avoid the problems of high loss and difficult filtration caused bythe use of zinc or aluminum alone. The intermediate frequency furnace is provided with mixing, so the heating is fast, the efficiency is high and the energy is saved. Toxic gases are not used, so thesafety is high. The recovery rate is improved through recycling and multiple filtration. Other metal resources can be recycled again to avoid waste.

Description

technical field [0001] The invention relates to a method for extracting osmium, iridium and ruthenium, in particular to a method for recycling precious metals in osmium-iridium-ruthenium ore. Background technique [0002] Zinc, aluminum or a mixture of the two are used for shredding. If zinc is used alone, the zinc oxide formed at high temperature will be seriously burned and the shredding effect will be poor; A large amount of reagents are consumed, and the leaching solution needs a large amount of water to dilute the concentration of aluminum, otherwise it cannot be filtered, and alkaline leaching to remove aluminum requires heating, otherwise it will take a long time and the leaching will not be complete. [0003] The patent (Application No. 01131879.1) proposes co-crushing with zinc and aluminum alloy. The crushing conditions are not specified in the patent, but the patent inventor's paper "Extracting Precious Metals from Ruthenium-Iridium-Osmium Ore Scale Production" wr...

AI Technical Summary

Problems solved by technology

Among them, it is evaluated that the speed of acid leaching to remove zinc and aluminum after crushing is slow, the efficiency is low, and the solid-liquid separation is difficult, but the principle and practice of the alkaline leaching used to remove aluminum should be more inefficient, and at the same time, the concentration of aluminum leaching solution is high and viscous. It cannot be filtered, and it needs to be diluted with a large amount of water when the leachate is in a hot state, so that it can be filtered smoothly

It evaluates that the traditional wet distillation consumes a large amount of expensive sodium bromate or sodium chlorate, but it uses chlorine gas as the oxidant instead. Chlorine gas is a poisonous and harmful gas and belongs to dangerous chemicals. Its purchase, transportation and storage require According to the "Regulations on the Safety Management of Hazardous Chemicals", the conditions for purchase and use are very strict, and the price is not cheap

Using sodium bromate, sodium chlorate or chlorine to distill osmium ruthenium, in fact, the distillation is not complete, the undistilled osmium ruthenium will exist in the residue, and the residue will be dissolved in aqua regia in the later stage of iridium extraction process, and part of the osmium ruthenium will be dissolved in aqua regia. Ruthenium will enter the solution and become an impurity during the purification of iridium. A part of osmium ruthenium including iridium will remain in the aqua regia insoluble residue. The aqua regia insoluble residue needs to be returned to alkali fusion for distillation, aqua regia dissolution and other steps.