Influence of 9% sodium hydroxide solution on kaolinite clay

Abstract

This study investigated the effect of sodium hydroxide (NaOH) solution on the surface characteristics and molecular structure of kaolinite clay. Scanning electron microscope coupled energy dispersive spectroscopy (SEM-EDS) and Fourier-transform infrared spectroscopy (FTIR) were employed in analyzing the raw and 9% NaOH-treated clay samples. The outcome of the SEM-EDS analysis showed a distinct difference between the raw and treated kaolinite clay samples in atomic concentration and weight concentration. In addition, the FTIR spectra of the raw clay exhibited characteristic peaks indicating the presence of O-H stretching vibrations and aromatic compounds. In contrast, the treated clay displayed new peaks suggestive of alkane groups and C-Cl stretching vibrations, indicating potential modifications induced by the NaOH solution treatment. These alterations in the chemical structure of the clay would have significant implications on the adsorption properties, particularly in the removal of contaminants from wastewater. Therefore, alkali-treated clay materials can be used as reinforcement in the production of nanocomposite for wastewater treatment processes.