Optimization of thorium solvent extraction and stripping processes from the leach liquor of thorium ore

This research investigates and optimizes the parameters of solvent extraction processes using thorium leach solutions from Chahghaz ore with D2EHPA. The effective parameters in the solvent extraction process were evaluated through experimental design to maximize thorium extraction and minimize iron extraction. Under optimum conditions—pH 0.6, extraction time of 2 minutes, 16% solvent concentration, and an organic-to-aqueous phase ratio of 1:2—thorium and iron recoveries were 99.47% and 9.60%, respectively. For the optimization of the stripping process, 89.75% thorium and 0.6% iron were recovered in 3.34 minutes with an organic-to-aqueous phase ratio of 2:1 and a sulfuric acid concentration of 3.9M.