1. College of Environmental Science and Engineering, Beijing Forestry University, 35 Qinghua East Road, Haidian District, Beijing 100083, P. R. China
2. Chemistry Department, Heterogeneous Catalysis Lab, University of Cyprus, 1 University Ave., University Campus 2109 Nicosia, Cyprus
3. Department of Chemical and Process Engineering, University of Surrey GU2 7XH Guildford, United Kingdom