The Optimization Of The Hydrogenation Reaction In The Preparation Of High Purity Lithium Carbonate With The Exception Of Calcium And Magnesium,

Lithium carbonate is a kind of basal Lithium salt and used as a feedstock to produce other lithium salts. In the early, there were a number of commercial applications of Lithium carbonate including: as additive in aluminium molten salt electrolysis and in enamels and glasses. Recently high purity lithium carbonate is not only required as anode and electrolyte in rechargeable lithium batteries, but also in medicines and surface stretch wave elements such as TL and NL.In this paper it presented the properties, applications of Li₂CO₃ and preparations of high purity Li₂CO₃. The process and mechanism of Lithium carbonate with carbon dioxide dissolved in aqueous solutions were researched. It included that the flux of CO₂ affected carbonation and how to control the flux of CO₂. It stressed the removal of Ca²⁺, Mg²⁺ from solutions with PUROLITE S-940 ion exchange resin. The high purity Li₂CO₃ was got .The best results showed as the following:1. The carbonation was pseudo first order reaction. The rate of reaction was determined by dissolution of CO₂ and transformation of Li₂CO₃.2. The flux of CO₂ affected the rate and efficiency of carbonation. The results showed that the best reaction conditions were at 2.667L·min^-1 flux of CO₂ if temperature was 20℃ and time was 90 min. The rate of reaction was the biggest. And the efficiency of carbonation was the highest.3. The removal of Ca²⁺, Mg²⁺ from solutions with PUROLITE S-940 ion exchange resin, the exchange capacity in dynamic mode was to 23.363 gCa·L^-1 resin. the exchange capacity in static mode was to 21.387 gCa·L^-1 resin.4. The concentration of Ca²⁺, Mg²⁺ and flux of solution affect the capacity of resin. At certain pH and temperature, the exchange velocity and capacity was obtained at 25.1796 mg·L^-1(Ca²⁺) and 16.8764 mg·L^-1(Mg²⁺) and at 15 BV·h^-1.5. The generation of resin was practiced in dynamic flow mode and properties were renewed efficiently.6. After removing Ca²⁺, Mg²⁺, B and vaporizing the solutions, the high purity Li₂CO₃ was got. The impurity contents accorded with GB10576-89.The Li₂CO₃contents were beyond 99.9 %.