Removal of lithium from water by aminomethylphosphonic acid-containing resin

Abstract

This study gives an overview of the ability of aminomethylphosphonic acid containing chelating resin for the removal of lithium (Li+) from water. Studies were performed under various conditions such as resin dose, initial Li+ concentration, solution pH and solution temperature. Results showed that the sorption of Li+ reached equilibrium within 15 min and the experimental data were well fitted by the pseudo-second-order kinetic model. The Li+ sorption was highly pH dependent, and the optimum pH for Li+ removal was ≥3. Isotherm sorption data displayed good correlation with the Langmuir model, and maximum monolayer sorption capacity of resin found as 13.65 mg/g. Thermodynamic studies suggested that Li+ sorption onto chelating resin was an exothermic and spontaneous process in nature. Resin can be regenerated by 0.1 M HCl, NaCl or H2SO4 with > 99 % efficiency. Desorption of Li+ with 0.1 M NaCl resulted in no changes of the uptake capacity through four subsequent sorption/desorption cycles

Keywords

• chelating resin
• ion exchange
• lithium
• lewatit TP260