Recovery method of waste rare earth polishing powder

Abstract

A recovery method of waste rare earth polishing powder comprises the following steps: weighing waste rare earth polishing powder, a reducing agent and strong base according to a ratio, uniformly mixing, and carrying out a reduction reaction at 600-800 DEG C for 60-240 min to obtain a reduction product; carrying out water quenching on the reduction product to room temperature to obtain a cooled product; carrying out hydrocyclone separation on the cooled product to obtain a mixture of a rare earth-rich material and a silicate aqueous solution and metallic lead; and filtering the mixture of the rare earth-rich material and the silicate aqueous solution to obtain the silicate aqueous solution and the rare earth-rich material. The pollution of lead in the waste rare earth polishing powder to the environment is solved, and resource utilization of valent rare earth, lead and silicon in the waste rare earth polishing powder is realized. The content of lead in the rare earth-rich material after the technical treatment is negligible. Leaching toxicity of heavy metal in the rare earth-rich material meets the national standard, and harmless, reduction and resource treatment of the waste rare earth polishing powder are realized. The method is in line with the goals of our national circular economy development and energy conservation and emission reduction.

Description

[0001] Technical field: [0002] The invention belongs to the technical field of hazardous solid waste treatment, and in particular relates to a recovery method of waste rare earth polishing powder. [0003] Background technique: [0004] The most important process in material surface processing technology is the polishing process, and polishing powder is one of the key materials in the polishing process, which has a great impact on the quality of the polished product. As an important optical glass polishing material, rare earth polishing powder has many advantages, such as: good crystal shape, good chemical activity, high density and hardness, high polishing efficiency, stable layer photometry and long service life, so it is called "King of polishing powder", and gradually replaced other polishing powder materials and has developed rapidly in the polishing industry. It is widely used in the fine grinding of optical and photoelectric glass, jewelry, building materials, molds an...

AI Technical Summary

Problems solved by technology

This patent requires harsh reaction conditions such as high temperature conditions (temperature is 1000°C) and vacuum (system pressure is 10Pa) and supporting production equipment, so it is difficult to realize industrial production

What the Chinese patent (publication number is CN102051487A) describes is to mix waste CRT glass powder, activated carbon and strong alkali, and after melting and reacting, separate crude lead, lye and alkali slag, then use dilute hydrochloric acid to soak the alkali slag to extract the residual lead, this patent does not reduce lead through deep reduction technology, but also needs to use hydrochloric acid to post-treat the alkali slag, which consumes a lot of hydrochloric acid

After analysis, this patent is not applicable to the separation of rare earth, metal lead and silicon

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