1. Department of Environmental Engineering, North China Electric Power University, 689 Huadian Road, Baoding, Hebei 071003, P. R. China
2. Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P. R. China
3. Department of Chemical Engineering, University of New Brunswick, Fredericton, New Brunswick E3B 5A3, Canada