1. Shandong Provincial Key Laboratory of Oilfield Produced Water Treatment and Environmental Pollution Control, (Hekou Oil Production Plant, Shengli Oilfield Branch of Sinopec), Dongying 257026, Shandong Province, P.R. China
2. Shandong Provincial Key Laboratory of Oilfield Produced Water Treatment and Environmental Pollution Control, (Sinopec Petroleum Engineering Corporation), Dongying 257026, Shandong Province, P.R. China
3. School of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou 221116, Jiangsu Province, P.R. China