• 责任者：Hao Yanling (School of Chemical and Biological Engineering ; Lanzhou Jiaotong University ; Lanzhou 730070 ; China) ; Dong Ming
• 刊名：Acta Petrologica et Mineralogica
• 出版年：2013
• 卷期：33(6)
• 页码：p.947-951
• issnNo：ISSN1000-6524
• isbnNo：CN11-1966/P

The palygorskite clay coated with iron oxide was prepared as the adsorbent and the adsorption properties and mechanisms of adsorbing Cr （Ⅵ） were investigated,with a discussion on the adsorption kinetics and thermodynamic characteristics.The results demonstrate that the adsorption function of Cr （Ⅵ） on modified palygorskite decreases significantly with increasing pH.The equilibrium can be reached in about 90 minutes and the adsorption processes seem to follow pseudo-second-order equation most effectively at an optimum pH of 4.0,the rate constant increases with the rise of temperature and the adsorption activation energy is 18.90 kJ/mol.Adsorption isotherms fit Langmuir equation fairly well,the adsorption enthalpy is 28.29 kJ/mol and the adsorption Gibbs free energy changes are in the range of-25 ～-20 kJ/mol.The adsorption process is endothermic and spontaneous,with the coexistence of physical adsorption and chemical adsorption.