Recovery method for front-section defluorination of waste lithium ion battery

Abstract

The invention relates to a recovery method for front-section defluorination of a waste lithium ion battery and a defluorination treatment method for the recovery front-section of the waste lithium ionbattery. The defluorination treatment method comprises the following steps of mixing the fluorine-containing battery powder with a fluorine dissolving aid solution, heating, stirring and filtering toobtain the defluorinated battery powder and the fluorine-containing washing liquor; adding a lithium precipitation agent into the fluorine-containing washing liquid, heating, stirring and filtering to obtain the lithium-containing slag and the lithium-removed liquid; adding a fluorine removal agent into the lithium-removed solution, stirring and filtering to obtain the fluorine-containing slag and the fluorine-removed solution; and preparing the defluorinated solution into a fluorine-dissolving auxiliary solution, and repeating the steps. By adopting the method disclosed by the invention, thefluorine content of the waste lithium ion battery can be reduced to be less than 0.11% before the waste lithium ion battery enters a recovery process, the fluorine removal rate is up to 90%, a seriesof problems caused by fluorine in a battery recovery process can be favorably solved. The method has high cyclic utilization rate of a washing liquid, great reduces the use amount of water, saves thecost, and has the great application prospect.

Description

technical field [0001] The invention belongs to the technical field of waste battery material recovery, and relates to a recovery method for removing fluorine from the front end of a waste lithium ion battery. Background technique [0002] Lithium-ion batteries were successfully developed in 1990. It is to embed lithium ions into carbon to form negative electrodes, replacing the metal lithium or lithium alloy negative electrodes of traditional lithium batteries. The negative electrode materials are mainly petroleum coke and graphite, which not only maintains the advantages of high specific energy and high specific power of lithium batteries, but also replaces the deposition and dissolution process on lithium electrodes due to the intercalation-intercalation process of lithium ions on carbon negative electrodes. The problem of dendrite penetration of lithium generated on the surface of the negative electrode is avoided, thereby ensuring the safety of the battery. Lithium-ion...

AI Technical Summary

Problems solved by technology

The disadvantages of post-stage fluoride removal include: (1) During the recovery process of valuable metals, the concentration of various ions in wastewater will gradually increase, resulting in poor post-stage fluoride removal effect, increased use of auxiliary materials, and a large amount of entrained fluoride slag (2) The fluorine in the lithium-ion battery enters the solution together with various metals during the leaching process, which will accelerate the corrosion of the equipment; (3) The fluorine ion and other ions in the solution can form stable compounds, It is easy to cause pipeline blockage; (4) fluorine will enter the stripping solution of P-204 in the extraction section, and the continuous enrichment cycle will cause fluorine to be entrained into the product during the extraction process, thus affecting product quality

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