1. School of Earth and Environment, Anhui University of Science and Technology, Huainan 232001, P. R. China
2. School of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001, P. R. China
3. Institute of Environment-friendly Materials and Occupational Health of Anhui University of Science and Technology (Wuhu), Wuhu 241003, P. R. China