Microwave-assisted atmospheric alkaline leaching process and leaching kinetics of rare earth melt electrolysis slag
Yusufujiang Mubula,
Mingming Yu,
Delong Yang,
Heyue Niu,
Hongju Gu,
Tingsheng Qiu,
Guangjun Mei
Affiliations
Yusufujiang Mubula
Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources, Jiangxi University of Science and Technology, Ganzhou, 341000, China
Mingming Yu
Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources, Jiangxi University of Science and Technology, Ganzhou, 341000, China; School of Resources and Environmental Engineering, Jiangxi University of Science and Technology, Ganzhou, 341000, China; Corresponding author. Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources, Jiangxi University of Science and Technology, Ganzhou, 341000, China.
Delong Yang
Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources, Jiangxi University of Science and Technology, Ganzhou, 341000, China
Heyue Niu
Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources, Jiangxi University of Science and Technology, Ganzhou, 341000, China
Hongju Gu
Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources, Jiangxi University of Science and Technology, Ganzhou, 341000, China
Tingsheng Qiu
Jiangxi Provincial Key Laboratory of Low-Carbon Processing and Utilization of Strategic Metal Mineral Resources, Jiangxi University of Science and Technology, Ganzhou, 341000, China; School of Resources and Environmental Engineering, Jiangxi University of Science and Technology, Ganzhou, 341000, China
Guangjun Mei
School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, China
This study focuses on the difficulty of converting fluorinated rare earth elements into hydroxylated rare earth elements in rare earth melt electrolysis slag (RMES) and proposes the use of a microwave-assisted atmospheric alkaline leaching method for the treatment of RMES. The leaching behavior of RMES under microwave-assisted atmospheric alkaline leaching was studied, and the optimal reaction conditions were determined. Under the conditions of a reaction temperature of 150 °C, initial NaOH concentration of 60 %, NaOH-to-slag mass ratio of 4:1, microwave power of 700 W, reaction time of 120 min, and stirring speed of 300 r/min, the conversion rate of fluorinated rare earths reached 99.17 %. The apparent rate equation of the microwave-assisted atmospheric alkaline leaching process was obtained by leaching kinetic analysis, and the apparent activation energy under this process was calculated to be 54.872 kJ/mol, which was 12.458 kJ/mol lower than that achieved when conventional heating was used for leaching (67.33 kJ/mol).
