Sorption methods of processing of hydromineral lithium raw material of Kazakhstan

Abstract

In the contemporary world of high technologies lithium (Li) is a key component. Kazakhstan has the required potential for its production. The most attractive raw materials for lithium extraction are natural and saline lake brines. Investigation and search of new technological solutions with the purpose of inclusion thereof in the sphere of lithium-containing hydromineral raw material processing is an important and relevant scientific and technical task. This article provides analysis of the literature data on lithium sorption by organic resins and inorganic sorbents. Generally, cation exchange resins, both in protonated and sodium forms, are mostly used for lithium sorption. They include widespread cationite KU-2-8 or its equivalents. In the investigations on lithium sorption extraction from lithium-containing solutions from amongst of inorganic sorbents mainly manganese, titanium and aluminum based compounds are used. For the static lithium extraction from natural brines we performed sorption using ionexchange resins: CU-2-8, Purolite ?100, Purolite C160S, Purolite S940, Amberlite IR 120, CYBBER CRX 210, and CYBBER CRX 300. It was demonstrated that almost no lithium is sorbed on ionites. Insignificant amount of lithium was extracted on sulphocationite CU-2-8 and made up 0.49%. Investigations were made on natural brines processing using inorganic sorbents (in the form of commercial reagents): aluminum hydroxide, titanium and manganese oxides, and activated carbon. Besides, such inorganic sorbents as aluminum hydroxide, hydrated titanium and manganese oxides were synthesized. It was established that the highest rates were achieved when aluminum hydroxide was used as sorbent, at that lithium extraction made up 21.87%, and on synthesized sorbent - hydrated manganese oxide, where Li extraction reached 20.11%. For lithium extraction from brines inorganic sorbents were chosen as the sorption method using aluminum and/or manganese compounds as sorbents.