Column leaching of lanthanides from Abu Tartur phosphate ore with kinetic study

The dynamic leaching of lanthanides from a west desert phosphate ore, Egypt (Abu Tartur) by hydrochloric acid, nitric acid and sulfuric acid solutions was investigated in this study as a function of acid concentration, flow rate and the presence of some additives such as boric acid. Also the kinetics of leaching of lanthanides was investigated as a function of temperature. It was found that the leaching process could be described by a shrinking-core model, with activation energy about 5.9, 13.8 and 21.9 kJ/M for leaching by HCl, HNO3 and H2SO4, respectively. Based on the experimental results, an empirical equation related to the rate constant of lanthanides leaching to leaching temperature was established for the purpose of process design.