2results about How to "Less impurity ions" patented technology

The invention relates to the technical field of lithium ion battery recovery, in particular to an electrochemical recovery method of a retired lithium iron phosphate battery, which comprises the following steps: preparing an electrode and constructing an electrolytic tank; performing an electrochemical leaching lithium extraction reaction and a circulating experiment; lithium precipitation and anode recovery; and regenerating the electrolyte. According to the method, the retired lithium iron phosphate battery electrode material is recycled by adopting an electrochemical selective leaching lithium extraction technology, the recovery rate of lithium can reach 89% or above, the recovery rate of iron phosphate can reach 90% or above, the regeneration rate of an anode side electrolyte and a cathode side electrolyte can reach 95% or above, and the selectivity of lithium leaching can reach 900 or above.

This invention belongs to the field of ceramic membranes and electronic chemical recycling, specifically relating to a method for preparing an ultraporous ceramic membrane for NMP purification. The method includes the following steps: (1) pretreatment of the ceramic membrane; (2) modification treatment of the ceramic membrane; and (3) preparation of the ultraporous ceramic membrane for NMP purification. Compared with existing technologies, the advantages of this invention are: 1) This invention can efficiently purify NMP from NMP waste liquid with different impurity contents, has a wide range of applications, and does not generate new pollutants during the entire process. The process is mature and stable and can be applied to the recycling and comprehensive treatment of various NMP-containing waste liquids. 2) This invention uses specific ultraviolet (UV) light irradiation conditions to modify the ceramic membrane surface. The surface grafting polymerization technology mainly focuses on the formation of active centers. Furthermore, the UV grafting modification only occurs on the surface of the ceramic membrane material and does not damage the internal structure of the ceramic membrane material. The ceramic membrane has good stability, high purity of NMP waste liquid recovery, and few impurity ions.