1. School of Environmental and Chemical Engineering
2. Foshan University
3. Foshan 528225
4. P. R. China
5. Guangdong Province Key Laboratory of Rare Earth Development and Application
6. Institute of Rare Metals, Guangdong Academy of Sciences
7. Guangzhou 510651
8. School of Chemical Engineering and Technology
9. Sun Yat-sen University
10. Zhuhai 519082