Spectroscopic study on variations in illite surface properties after acid-base titration
FT-IR, Raman microscopy, XRD, 29 Si and 27 Al MAS NMR, were used to investigate changes in surface properties of a natural illitesample after acid-base potentiometric titration. The characteristic XRD lines indicated the presence of surface Al-Si complexes, preferable to Al(OH)3 precipitates. In the microscopic Raman spectra, the vibration peaks of Si-O and Al-O bonds diminished as a result of treatment withacid, then increased after hydroxide back titration. The varied ratio of signal intensity between Ⅳ Al and Ⅵ At species in 27 Al MAS NMRspectra, together with the stable BET surface area after acidimetric titration, suggested that edge faces and basal planes in the layer structure ofillite participated in dissolution of structural components. The combined spectroscopic evidence demonstrated that the reactions between illitesurfaces and acid-leaching silicic acid and aluminum ions should be considered in the model description of surface acid-base properties of theaqueous illite.
作 者： LIU Wen-xin COVENEY R.M TANG Hong-xiao 作者单位： LIU Wen-xin,TANG Hong-xiao(SKLEAC, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 China)COVENEY R.M(Department of Geosciences, University of Missouri-Kansas City, 420D Robert H. Flarsheim Hall, 5100 Rockhill Road, Kansas City, Missouri 64110-2499)
刊 名： 环境科学学报(英文版) ISTIC SCI 英文刊名： JOURNAL OF ENVIRONMENTAL SCIENCES 年，卷(期)： 2003 15(4) 分类号： X13 关键词： natural illite acid-base titration spectroscopic information surface Al-Si species surface complexation