METHODS FOR PREPARING TWO-DIMENSIONAL SHEET-LIKE Li4SiO4 ADSORBENTS USING ATTAPULGITE AND WASTE LITHIUM BATTERIES

A method for preparing two-dimensional sheet-like LiSiOsorbent, including: obtaining LiCoOby performing discharging, aluminum foil stripping, and sieving on waste lithium battery cathode material, and drying; obtaining biomass by freeze-drying waste biomass, and grinding and sieving the freeze-dried waste biomass; mixing LiCoOand the biomass uniformly to obtain a mixture, and putting the mixture into a tube furnace for nitrogen purging, heating and calcination, and carbothermal reduction to obtain a solid sample, hydrothermal stirring the solid sample, followed by filtering, and evaporating to obtain LiCO; ultrasonically dispersing the attapulgite in an acid solution, and stirring in a water bath at 80° C. to obtain a first product, washing the first product until neutrality, filtering, and drying overnight to obtain SiO; and ultrasonically dispersing the weighed SiOin deionized water, adding NaOH for hydrothermal stirring, adding the obtained LiCOfor stirring reaction, adding NHF, and dropwise adding ammonia water to adjust pH of a solution, transferring the solution to a microwave hydrothermal reaction kettle for microwave hydrothermal reaction to obtain a second product, and centrifuging, washing, drying, and calcining the second product to obtain the two-dimensional sheet-like LiSiO.