The Spectroscopy Characterization of Kaolinite-Organic Intercalation Materials

Abstract

Kaolinite/formamide intercalation materials are characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy(FT-IR), Raman spectroscopy and 1H magic angle spinning nuclear magnetic resonance spectroscopy (1H MAS NMR). The d(001) spacing of kaolinite treated with formamide is 1.020nm, which is larger than that of the original clay. The 1H MAS NMR graphs show that the proton chemical shifts of the inner hydroxyl and inner surface hydroxyl of kaolinte are δ-1.3 and δ2.4 respectively. After formamide intercalation, the proton peaks of the inner surface hydroxyls shifted to high-field with δ2.3, the proton peak of the inner hydroxyl shifted to δ-0.3 toward low-field. In the hydroxyl stretching vibration region of Raman spectrum, the formamide intercalation resulted in the decrease of the intensities of kaolinite inner surface hydroxyl bands at 3699cm-1,3682cm-1, 3665cm-1 and 3642cm-1, and the appearance of additional bands at 3610cm-1,3628cm-1. In the NH stretching region of FT-IR spectrum, two bands are observed at 3336cm-1 and 3466cm-1 corresponding to the two types of the hydrogen bonds between formamide and kaolinite. In the carboxyl stretching region, an additional band at 1667cm-1 is assigned to C=O group that bonded to the inner surface hydroxyl of kaolinite.