1. School of Chemical Engineering and Technology; Xi'an Jiaotong University; Xi'an Shaanxi 710049 P.R. China
2. State Key Laboratory of Catalytic Materials and Reaction Engineering; Research Institute of Petroleum Processing, Sinopec; Beijing 100083 P.R. China
3. School of Chemical Engineering; China University of Mining and Technology; Xuzhou Jiangsu 221116 P.R. China