The kinetics and thermodynamics investigation of lithium extraction from brine by TBP using Lewis cell technique

Abstract

The extraction kinetics of lithium from brine by tri-n-butyl phosphate had been researched experimentally using Lewis cell technique. Different parameters such as interfacial area, temperature, agitation speed, the concentration of Li+, Fe3+ and TBP were studied separately to identify the reaction location and the extraction reaction regime. The experimental results demonstrated the control mode of the extraction reaction was a mixed control mode which occurred at the interfacial area. Further analysis suggested the extraction rate equation can be expressed as follows: R=3.145×10-3[Li+][FeCl4-][TBP]2The results of thermodynamic functions suggested the extraction reaction was an entropy increase process and extraction reaction was spontaneous.