Investigation of physico-chemical properties of montmorillonite modified with cationic surfactant

In this study, montmorillonite (MMT) was modified by hexadecyltrimethyl ammonium bromide (HDTMA) to enhance its adsorption capacity and improve its functional properties that it was done through conventional ion exchange. The intercalation of cationic surfactant into layers of MMT and properties of MMT before and after modification was evaluated by Fourier transform infrared (FTIR), X-ray diffraction (XRD) spectroscopy, Thermal gravimetric analysis, contact angle, and zeta potential. The XRD results showed the interlayer spacing was increased from 1.17 to 2.02 nm due to intercalation of HDTMA. The contact angle and zeta potential analyses revealed that the surface wettability of MMT was changed from hydrophilic to hydrophobic and the surface charge was changed from -21.6 to -2.54 due to adsorption of HDTAM on surface of MMT. FTIR spectra show the successful of inserting alkyl groups from cationic surfactant in the interlayer space of MMT. The results are supported by the measurements of TGA/DTA. The findings of this study are useful for the application of modified MMT as a nanoadsorbent for food, chemical, and pharmaceutical industries.