中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 26 No. 11 November 2016 |
(1. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China;
2. Key Laboratory for Green Chemical Process of Ministry of Education,
Wuhan Institute of Technology, Wuhan 430073, China)
Abstract:In order to better understand the leaching process of rare earth (RE) and aluminum (Al) from the weathered crust elution- deposited RE ore, the mass transfer of RE and Al in column leaching was investigated using the chromatographic plate theory. The results show that a higher initial ammonium concentration in a certain range can enhance the mass transfer process. pH of leaching agent in the range of 2 to 8 almost has no effect on the mass transfer efficiency of RE, but plays a positive role in the mass transfer efficiency of Al under strong acidic condition (pH<4). There is an optimum flow rate that makes the highest mass transfer efficiency. The optimum leaching condition of RE is the leaching agent pH of 4-8, ammonium concentration of 0.4 mol/L and flow rate of 0.5 mL/min. The mass transfer efficiencies of RE and Al both follow the order: (NH4)2SO4<NH4Cl<NH4NO3, implying the complexing ability of anion.
Key words: column leaching process; weathered crust elution-deposited rare earth ore; rare earth; aluminum; ammonium salt; mass transfer