Investigation of TiO₂-Impregnated Laterite (TIL) as an Adsorbent for Arsenic Removal in Aqueous Media

This study investigates the potential of TiO₂-impregnated laterite (TIL) as a cost-effective and sustainable adsorbent for arsenic removal from aqueous solutions. A Box–Behnken design within the framework of Response Surface Methodology (RSM) was employed to optimize three key operational parameters: adsorbent dosage, solution pH, and contact time. The TiO₂-laterite composite was synthesized through impregnation, aging, and calcination processes to enhance adsorption capacity. Experimental results indicated that adsorbent dosage and reaction time had significant effects on arsenic removal efficiency, whereas pH had a minor influence within the tested range. The optimal conditions—0.99 g dosage, pH 5.3, and 71 minutes contact time—yielded an arsenic removal efficiency of 97.65%, closely aligning with the model-predicted value of 98.82%. ANOVA analysis confirmed the significance of the fitted quadratic model (R² = 0.996). The findings demonstrate that TiO₂-impregnated laterite is a promising material for arsenic remediation, offering high performance, economic feasibility, and scalability. However, further research is needed to validate performance under field conditions, analysis material characterization, assess long-term stability, and explore regeneration capacity.