1. National Engineering Research Center of Coal Preparation and Purification, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
2. School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
3. Binnan Oil Recovery Plant of Shengli Oil Field, China Petrochemical Corporation, Binzhou, Shandong 256606, China