地质学报（英文版）2006，Vol.80Issue(2)：192-199,8.
Adsorption of Pentachlorophenol onto Oxide and Clay Minerals: Surface Reaction Model and Environmental Implications
Adsorption of Pentachlorophenol onto Oxide and Clay Minerals: Surface Reaction Model and Environmental Implications
摘要
Abstract
The adsorption of pentachlorophenol (PCP) onto quartz, kaolinite, illite, montmorillonite and iron oxides has been investigated by batch equilibrium techniques. The pH-dependent isotherms are curves with peak values, the position of which is at about pH= 5-6 depending on the mineral species. Based on distribution of both speciation of surface hydroxyls on minerals and PCP in solution a surface reaction model involving surface complexation and surface electrostatic attraction is presented to fit the pH-dependent isotherms, and both reaction constants are calculated. The results show that on quartz and phyllosilicate minerals the predominant adsorption reaction is surface complexation,meanwhile both of surface electrostatic attraction and surface complexation are involved on the iron oxide minerals. The reaction constants of surface electrostatic adsorption are usually one to three orders in magnitude, larger than that of surface complexation. The concentration-dependent isotherms can be well fitted by Langmuir equation with the correlation coefficient R＞0.93 for kaolinite and iron oxides. The maximum adsorption is found in the order: hematite ＞ lepidocrocite ＞ goethite ＞ kaolinite ＞quartz ＞ montmorillonite ≈ illite, which can be interpreted by consideration of both reaction mechanism and surface hydroxyl density. The significant adsorption of PCP onto mineral surfaces suggests that clay and iron oxide minerals will play an important role as HIOCs are adsorbed in laterite or latertoid soil, which is widespread in South China.关键词
pentachlorophenol (PCP)/adsorption/quartz/kaolinite/montmorillonite/illite/iron oxides/surface reaction modelKey words
pentachlorophenol (PCP)/adsorption/quartz/kaolinite/montmorillonite/illite/iron oxides/surface reaction model分类
天文与地球科学引用本文复制引用
WU Daqing,DIAO Guiyi,YUAN Peng,PENG Jinlian..Adsorption of Pentachlorophenol onto Oxide and Clay Minerals: Surface Reaction Model and Environmental Implications[J].地质学报（英文版）,2006,80(2):192-199,8.基金项目
The present work was financially supported by the National Natural Science Foundation of China (grant No.40373045), the Natural Science Foundation of Guangdong Province, China (grant No. 030461) and the Chinese Academy of Sciences Innovation Project (GIGCX-04-02).We are grateful to He Hongpin and Wang Yangchun forsupplying the clay mineral samples. （grant No.40373045）
