Assessment of 6% and 12% NaOH-treated clay samples for composite application in wastewater treatment

Abstract

The present study aims to modify the surface characteristics of locally sourced kaolinite clay using 6% and 12% NaOH solution. The effect of NaOH activation on the surface characteristics, elemental composition and structure of the clay samples was investigated using scanning electron microscope coupled elemental dispersive X-ray spectroscopy (SEM-EDS) and Fourier transform infrared spectrometer (FTIR) techniques. The FTIR graphs showed that the intensity of the bands decreases with the concentration of NaOH. Furthermore, the SEM images revealed that the treated clay samples showed distinctive particle characteristics compared to the untreated sample. Thereby, improving the surface area and creating a rough surface topography that could enhance the adsorption of heavy metals in wastewater remediation and clay matrix interface polymer. Overall, the NaOH activation process improved the crystallinity of the treated samples. Additionally, the EDS analysis revealed that silicon, aluminium and iron were the prominent elements. These findings have proven the capability of NaOH-treated clay for use in wastewater remediation.