An excellent extraction selectivity towards Sc over other REEs in 4 mol/L HCl solution was achieved with the separation factor βSc/REEs over 8000 by 2-ethylhexyl phosphoric acid mono 2-ethylhexyl ester(HEHEHP)and the...An excellent extraction selectivity towards Sc over other REEs in 4 mol/L HCl solution was achieved with the separation factor βSc/REEs over 8000 by 2-ethylhexyl phosphoric acid mono 2-ethylhexyl ester(HEHEHP)and the extraction equilibrium can be obtained within 20 min.The extracted Sc can be stripped using 5 mol/L NaOH solution as eluent at 363 K with the stripping rate of 92.1%obtained.The extraction mechanism was clearly elucidated by slope analysis,saturation extraction,IR,and NMR analysis.It was revealed that the extraction of Sc in 4 mol/L HCl solution is still dominated by cation exchange process between P-O-H and Sc,and coordination process between P=O and Sc,with 6 molecules of extractant as dimer participating in the process.Finally,a flowsheet for the recovery of Sc from ion-adsorption rare earth elements(REEs)concentrate was proposed and proved in lab-scale experiment.展开更多
基金Projects(11705032,11975082,U1967218)supported by the National Natural Science Foundation of ChinaProject(2017GXNSFBA198175)supported by the Natural Science Foundation of Guangxi Province,ChinaProject(AA17204100)supported by the Science and Technology Major Project of Guangxi Province,China。
文摘An excellent extraction selectivity towards Sc over other REEs in 4 mol/L HCl solution was achieved with the separation factor βSc/REEs over 8000 by 2-ethylhexyl phosphoric acid mono 2-ethylhexyl ester(HEHEHP)and the extraction equilibrium can be obtained within 20 min.The extracted Sc can be stripped using 5 mol/L NaOH solution as eluent at 363 K with the stripping rate of 92.1%obtained.The extraction mechanism was clearly elucidated by slope analysis,saturation extraction,IR,and NMR analysis.It was revealed that the extraction of Sc in 4 mol/L HCl solution is still dominated by cation exchange process between P-O-H and Sc,and coordination process between P=O and Sc,with 6 molecules of extractant as dimer participating in the process.Finally,a flowsheet for the recovery of Sc from ion-adsorption rare earth elements(REEs)concentrate was proposed and proved in lab-scale experiment.
