NMOSI SARAH OZAOMA

This study focused on the photodegradation of cassava wastewater. The potential use of titanium dioxide, periwinkle shell and roof tiles, a sustainable and biodegradable catalyst to adsorb the pollutant from the aqueous solutions was investigated. The catalyst was prepared by calcination and characterised by X-ray fluorescence (XRF), Brunauer-Emmet-Teller (BET), Scanning Electron Microscopy (SEM) and Fourier transform infrared spectrometry (FTIR) analysis. In this study, we explore the viability of using both activated and unactivated periwinkle shell and roof tiles powder to effectively the contaminants from the cassava wastewater. During the degradation process, the effects of some process variables such as contact time, concentration of the wastewater, and catalyst dose were investigated. The results of batch adsorption study showed that for unmodified and modified catalyst, increasing the catalyst dosage and contact time resulted in increased percentage removal while increasing the concentration lead to a decrease in percentage removal. The optimum conditions for maximum percentage removal for unmodified and modified adsorbent are 3g catalyst dosage, 150 minutes contact time, and 100ml/l concentration of the wastewater. For adsorption Isotherm, Langmuir model was the best model for modified catalyst with a correlation coefficient of r2 ≥ 0.2989 and in comparing the correlation coefficient r2 obtained from the Langmuir and Freundlich model, it clearly shows that the experimental analysis fit Freundlich model with r 2 ≥ 0.8742 for unmodified catalyst. For adsorption kinetics, Pseudo second order reaction showed a better fit (r2 ≥ 0.9999, r2 ≥ 0.9998) than both Langrande pseudo first-order (r2 ≥ 0.9782, r2 ≥ 0.9982) and the intra particle diffusion (r2 ≥ 0.9552, r2 ≥ 0.9494) for the modified and unmodified catalyst.