1. Department of Environmental Engineering, College of Environmental Science and Engineering, Guilin University of Technology , Guilin , 541006 , China
2. Department of Environmental Engineering, School of Metallurgy and Environment, Central South University , Lushan South Road 932 , Changsha 410083 , China
3. Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution , Lushan South Road 932 , Changsha Hunan 410083 , China