Structural Model and De-Intercalation Kinetics of Kaolinite-Methanol-Sodium Stearate Intercalation Compound

Journal of the Brazilian Chemical Society

Cheng, Hongfei¹  China University of Mining & Technology, Beijing, China¹  Liu, Qinfu¹  Wang,, Sen¹  Zuo,, Xiaochao¹  Yang, Yongjie¹ 

关键词:  kaolinite;    sodium stearate;    intercalation;    structural model;    kinetic;   

DOI  :  10.5935/0103-5053.20160136

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

Kaolinite-methanol-sodium stearate intercalation compound (Ka-MeOH-SS) was prepared by intercalation of kaolinite with dimethyl sulfoxide (DMSO) followed by displacing of DMSO with methanol and methanol by sodium stearate. The sample was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermal analysis (thermogravimetry (TGA) and differential scanning calorimetry (DSC)) and transmission electron microscopy (TEM). The results show that the basal spacing of Ka-MeOH-SS was enlarged to 45.5-47.9 Å and parts of its layers cocked and curled. Stearate ions were grafted on the methoxy groups and arrayed aslant in the interlayer space of kaolinite with an inclination angle of 47.45º to 52.17º. Sodium ions were adsorbed around the SiO4 tetrahedron and interlayer carboxylate anions, whereas some of them entered into the ditrigonal hole of tetrahedral sheets. The thermal de-intercalation of Ka-MeOH-SS includes three steps and the activation energy E is 98.3 kJ mol−1, logarithm of pre-exponential factor lg(A / s-1 is 9.71 and the mechanism function is f(α) = −ln (1 − α) and G(α) = 1 − α.

【 授权许可】

Unknown