1. School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China
2. National Enterprise Technology Center, Inner Mongolia Erdos Electric Power and Metallurgy Group Co., Ltd, Inner Mongolia 016064, P. R. China
3. State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, P. R. China