(560fv) Fabrication of Natural Clay Based Nanocomposite Materials for Advanced Catalytic Treatment of Organic Pollutants in Wastewater

Natural clays are used in the fabrication of several materials for various industrial applications. This study investigates the fabrication of natural clay-based nanocomposite materials for catalytic removal of dye pollutants in wastewater. The materials were characterized for physical and mineralogical properties using various characterization techniques. X-ray spectroscopy (XRD and XRF) confirmed that the chemical composition was SiO₂, Al₂O₃, Fe₂O₃, K₂O and TiO₂ in the form of quartz, kaolinite, magnetite and illite. The BET showed that the fabricated materials are mesoporous indicating their potential application in wastewater. The presence of TiO₂ and added multi-walled carbon nanotubes (MWCNTs) contributed to the photoresponse of the materials. The natural nanocomposites revealed absorption in the visible range implying that these materials can be applied under the visible light irradiation. The energy band gap values were also relatively low 1.5 and 2.9 eV for the natural nanocomposite materials. Photodegradation was achieved with dyes used as pollutants model. The photodegradation was enhanced (95%) when MWCNTs were added to the natural clays. The addition of CNTs also led to the reduction of the holes-electrons pair recombination which improved the degradation activity of dye molecules from the increased presence of oxidizing species in aqueous solution. The total organic content removal value was quite high 85% and it confirmed the mineralization of the dye molecules. The findings demonstrate that natural clay and MWCNTs can be used successfully for the treatment of dyes wastewater. The implication of these data indicates that the natural nanocomposite materials can be optimized and deploy in the rural area, where natural clays are available and enough solar light can be harvest, for the treatment of wastewater to the benefit of the rural community.