Study On The Forming Process And The Lithium Extraction Technology Of The Lithium Ion Adsorbent With Metatitanic Acid Type

Nowadays,with the lithium battery industry rapidly developing,the relative raw materials have been in shortage and their prices soared.As a kind of environmental method to extract lithium,lithium adsorption had its unique advantages on the application of brine in China.But the difficulty of granulation?low strength,easy to wear?and the high loss in dissolution?single rate is higher than 1%?have restricted the pace of its industrial application.In this paper,based on the preparation of highly efficient lithium ion adsorbent with metatitanic acid type in our laboratory,the suitable molding method was explored and the molding conditions were optimized.The results showed that in methods we have chosen,the selection of modified cellulose is suitable,which used EC as a binder and used extrusion molding process.Granular adsorbent would be obtained which has the proper strength,lower abrasion rate and smaller adsorption capacity loss.What's more,the optimum conditions were shown:binder dosage is8%,the drying temperature is 65°C,pore forming agent KCl addition amount was1/10 of the binder and extrusion diameter is 1mm.Finally,the obtained granular adsorbent was solidified 1 hour in 120°C,and its static saturated adsorption capacity would be 19.73 mg/g.Through the study on the adsorption and desorption properties of obtained lithium ion adsorption agent with metatitanic acid type,we can find that its inert structure and morphology have not obvious change after the forming process.The adsorption desorption equilibrium time was 30 min and 20 min respectively.Therefore,its selectivity sequence of some main gold metal ions in brine was Li⁺>Mg²⁺>Na⁺>K⁺>Ca²⁺.Simultaneously,particle adsorption agent could keep good stability in all related media;its dissolution loss rate and wear rate was 0.050%and less than 20%respectively after cyclic adsorption-desorption 100 times.Finally,the lithium extraction process from simulated old brine was studied,using the prepared particle adsorbent,and then the reasonable process route of lithium carbonate production was determined.The results showed that adsorption and desorption liquid flow should be controlled 820 mL/h and 750 mL/h respectively,and the cycle should be five adsorption levels and two desorption levels.What's important,the effect of adsorption and extraction of lithium was still stable relatively when the cycle was going for 72h.In addition,the reasonable technological conditions for the preparation of lithium carbonate by the adsorption method were also determined in this paper.The process was clarified as below:removing most of magnesium by the lime method before adsorption,removing calcium and magnesium absolutely by phosphate after desorption and finally obtaining the production lithium carbonate by using soda precipitation method.The results showed that the lithium extraction rate was 96.77%.And the purity of Li2CO3 product was higher.The other data were in accordance with the standard of battery grade lithium carbonate,and the total yield was 88.40%.