Separation of indium(Ⅲ), gallium(Ⅲ), and zinc(Ⅱ) with Levextrel resin containing di(2-ethylhexyl) phosphoric acid (CL-P204): Part Ⅱ. Mechanism and kinetics of adsorbing indium(Ⅲ)

摘要

The mechanism of adsorbing indium(Ⅲ) from sulfate solutions with CL-P204 Levextrel resin containing di(-2-ethylhexyl) phosphoric acid was examined by batch operation and infrared spectra. The results showed that the P204 adsorbed on the resin behaved in the similar way to solvent extraction except that it was as a monomer in resin adsorbing but in dimeric form in solvent extraction. Three factors including temperature, indium(Ⅲ) concentration of solution, and the size of resin particles which influence the In3+/H+ exchange on CL-P204 Levextrel resin were investigated by the modified limited batch technique in order to determine the kinetics of In3+/H+ exchange. It was found that the rate of ion exchange increased with the temperature and the concentration of solution increasing and with the size of the resin particles decreasing.According to the expression developed by Boyd et al., the controlling factor of In3+/H+ exchange on CL-P204 Levextrel resin was the diffusion through the resin particles. The effective diffusion coefficient, activation energy, and entropy of activation in the particle-diffusion were determined as 1.57 x l0-10 m2/s, 11.9 KJ/mol, -84.1 J/(mol. K), respectively.