1. School of Chemical Engineering, Northwest University, Xi’an, Shaanxi 710069, P. R. China
2. Chemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei Energy, Xi’an, Shaanxi 710069, P. R. China
3. Shaanxi Research Center of Engineering Technology for Clean Coal Conversion, Xi’an, Shaanxi 710069, P. R. China
4. Shaanxi Key Laboratory of Physico-Inorganic Chemistry, Department of Chemistry, Northwest University, Xi’an, Shaanxi, 710069, P. R. China