高岭石
X射线光电子能谱
电位滴定法
傅里叶变换红外光谱
金属
无机化学
材料科学
分析化学(期刊)
打赌理论
化学
矿物学
离子
物理化学
化学工程
吸附
冶金
工程类
色谱法
有机化学
作者
Bo-Li Zhu,Chang-Lin Qi,Yunhui Zhang,Teresa M. Bisson,Zhenghe Xu,Yingju Fan,Zhong-Xi Sun
标识
DOI:10.1016/j.clay.2019.105138
摘要
Pure kaolinite and metal ion doped kaolinite were synthesized successfully for the first time with different M/Al (M = Mn, Fe, Co) ratios (0, 0.042, 0.087, 0.19) at 220 °C by the hydrothermal method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and BET techniques (N2/BET) were used for sample characterization. XRD patterns of the products showed that kaolinite was the only crystalline phase synthesized and the lattice parameters varied systematically with metal content. The surface acid-base properties of the pure kaolinite and doped kaolinite were studied by potentiometric titration. Surface site concentration (Hs) and surface site density (Ds) increased as metal ion content in the metal doped kaolinite increased. The relevant acid-base equilibrium constants of synthesized products were calculated by applying the constant capacitance model using computer software WinSGW. The surface pKa values of synthetic kaolinite were calculated as: logKa1 = 1.48; logKa2 = −7.03. The results showed that a small number of metal ions significantly affect the surface acid-base properties of kaolinite, which may explain the origin of variability of the reported surface pKa values of kaolinite.
科研通智能强力驱动
Strongly Powered by AbleSci AI