Preparation method of battery-grade anhydrous lithium hydroxide

[0037] Such as figure 1 Shown, the present invention proposes the preparation method of battery grade anhydrous lithium hydroxide, and this preparation method comprises:

[0038] Step S101, dissolving, adding industrial-grade lithium hydroxide monohydrate and ultrapure water to stir and dissolve completely, and making lithium hydroxide aqueous solution;

[0039] Step S102, ultrafiltration membrane filtration, passing the lithium hydroxide solution through the ultrafiltration membrane, and filtering to remove impurities;

[0040] Step S103, the resin absorbs and removes impurities, and the leaching solution is respectively subjected to adsorption and removal of impurities by chelating resin and strong basic anion resin;

[0041] Step S104, recrystallization, using the MVR forced circulation evaporation crystallization technology to evaporate and crystallize the LiOH solution to precipitate lithium hydroxide crystals;

[0042] Step S105, jet milling, jet milling the recrystallize

[0047] Dissolve 100kg of industrial-grade lithium hydroxide monohydrate in 1000L of pure water, stir and dissolve, then filter through an ultrafiltration membrane, and then adsorb and remove impurities through chelating resin and strong alkaline anions. 93 kg of refined lithium hydroxide monohydrate were obtained after MVR forced circulation evaporation and recrystallization, and D50 was 1.8 mm. Grinding with pre-treated air flow. Lithium hydroxide monohydrate with a D50 of 40um was obtained, dried in vacuum at 150°C for 3 hours, and iron was removed by using an electromagnetic iron remover to select a mesh-shaped magnetic inter-network under a magnetic field strength of 12000GS. Finally, the anhydrous lithium hydroxide product is obtained.

[0049] Dissolve 120kg of industrial-grade lithium hydroxide monohydrate in 1000L of pure water, stir and dissolve, filter through an ultrafiltration membrane, and then remove impurities by adsorption of strong alkaline ions. 110 kg of refined lithium hydroxide monohydrate were obtained after MVR forced circulation evaporation and recrystallization, and D50 was 2.1 mm. Grinding with pre-treated air flow. Lithium hydroxide monohydrate with a D50 of 33um was obtained, dried in vacuum at 160°C for 2 hours, and iron was removed by using an electromagnetic iron remover to select a meshed magnetic inter-network under a magnetic field strength of 10000GS. Finally, the anhydrous lithium hydroxide product is obtained.