A microwave-assisted leaching method of selenium and arsenic in copper anode slime

Abstract

The invention belongs to the technical field of wet metallurgy and specifically relates to a method for leaching selenium and arsenic in copper anode mud under assistance of microwave. The method comprises the steps of adding sodium hydroxide having the concentration of 40-160g / L to the screened copper anode mud for slurry mixing, controlling the weight concentration of the copper anode mud slurry within the range of 15%-45%, after slurry mixing, putting the slurry into a microwave reacting furnace at a microwave frequency within the range of 500-4000MHz, performing a leaching reaction under a normal pressure for 2-15 minutes and then discharging, and finally, performing solid-liquid separation to obtain a leachate containing selenium and arsenic. The leachate and the leaching residue obtained after the treatment by use of the microwave technology are easy to treat, and consequently, the subsequent noble metal extraction process can be greatly simplified, the production cost is low and the treatment time is short; the method is a green and environment-friendly pretreatment process.

Description

technical field [0001] The invention belongs to the technical field of hydrometallurgy, and in particular relates to a method for leaching selenium and arsenic in copper anode slime assisted by microwaves. Background technique [0002] Copper anode slime contains a large amount of precious metals, rare elements and platinum group metals, and is an important raw material for extracting rare and precious elements. In order to effectively extract the rare and precious elements of copper anode slime and facilitate the recovery of other valuable elements, it is necessary to pretreat the anode slime. The purpose of the pretreatment process is to remove copper, selenium, arsenic and other elements as much as possible and make the precious metal Enrichment, and then recover gold, silver and platinum group metals by fire method or wet method. For the pretreatment of copper anode slime to remove selenium and arsenic, many methods are currently used at home and abroad, such as sulfate...

AI Technical Summary

Problems solved by technology

In the pyrotechnic process, the roasting process has disadvantages such as high energy consumption, poor operating environment, poor adaptability of raw materials and environmental pollution, which is still a technical problem all over the world.

The traditional wet process has the advantages of being environmentally friendly, but at the same time has the disadvantages of low leaching rate, long reaction time, and low efficiency. It takes 8 hours or even longer to reach saturation, and the leaching rates of selenium and arsenic are low. All below 60%

[0003] When microwave-assisted leaching is used, the mineral is rapidly heated by microwave, and a large thermal stress is generated accordingly, and tiny cracks are also generated on the edge of the mineral, which further enhances the activity of the mineral, but also activates selenium and arsenic at the same time Other than metal element ions, there are disadvantages such as metal leaching and dispersion during acid leaching under microwave field, complex and difficult to handle leaching solution, etc.

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