Herein,palygorskite（PAL）was activated via a simple hydrothermal process in the presence of ammonium sulfide,and the effects of activation on the microstructure,physico-chemical feature and adsorption behaviors of PA...Herein,palygorskite（PAL）was activated via a simple hydrothermal process in the presence of ammonium sulfide,and the effects of activation on the microstructure,physico-chemical feature and adsorption behaviors of PAL were intensively investigated.The hydrothermal process evidently improved the dispersion of PAL crystal bundles,increased surface negative charges and built more active –Si–O-groups served as the new＂adsorption sites＂.The adsorption property of the activated PAL for Methyl Violet（MV）was systematically investigated by optimizing the adsorption variables,including p H,ionic strength,contact time and initial MV concentration.The activated PAL exhibited a superior adsorption capability to the raw PAL for the removal of MV（from 156.05 to 218.11 mg/g）.The kinetics for MV adsorption followed pseudo second-order kinetic models,while the isotherm and thermodynamics results showed that the adsorption pattern well followed the Langmuir model.The structure analysis of PAL before and after adsorption demonstrated that electrostatic interaction and chemical association of –X–O-are the prominent driving forces for the adsorption process.展开更多
基金supported by the“863”Project of the Ministry of Science and Technology,People's Republic of China(No.2013AA032003)the National Natural Science Foundation of China(No.51403221)
文摘Herein,palygorskite（PAL）was activated via a simple hydrothermal process in the presence of ammonium sulfide,and the effects of activation on the microstructure,physico-chemical feature and adsorption behaviors of PAL were intensively investigated.The hydrothermal process evidently improved the dispersion of PAL crystal bundles,increased surface negative charges and built more active –Si–O-groups served as the new＂adsorption sites＂.The adsorption property of the activated PAL for Methyl Violet（MV）was systematically investigated by optimizing the adsorption variables,including p H,ionic strength,contact time and initial MV concentration.The activated PAL exhibited a superior adsorption capability to the raw PAL for the removal of MV（from 156.05 to 218.11 mg/g）.The kinetics for MV adsorption followed pseudo second-order kinetic models,while the isotherm and thermodynamics results showed that the adsorption pattern well followed the Langmuir model.The structure analysis of PAL before and after adsorption demonstrated that electrostatic interaction and chemical association of –X–O-are the prominent driving forces for the adsorption process.
