Maximizing Anilinium Ionic Solid Mineralization Using RSM: A COD and TOC Study of Photocatalytic Degradation

The toxicity of anilinium-based compounds continues to increase with their prevalence in industrial effluents, posing a significant threat to aquatic ecosystems. To address this, a photocatalytic system comprising UV/H2O2/Ti-MOF was developed and optimized for the degradation of ionic solids (ISs). The synthesized Ti-MOF was characterized for its absorption and energy transmission capacity, morphological and elemental properties, thermal stability, and phase behavior, with UV-Vis, SEM-EDX, XRD, and TGA-DSC, respectively. The degradation experiment under UV irradiation in the presence of hydrogen peroxide (H2O2) and Ti-MOF illustrated an enhanced catalytic efficiency of the system when compared to blank experiments without the MOF catalyst. A response surface methodology (RSM) based on the Box–Behnken design (BBD) was then employed to evaluate and optimize key parameters, including IS concentration (150–650 mg/mL), time (1–5 h), and H2O2 (1–5%), in terms of the degradation efficiency. At optimal conditions for an IS concentration of 650 mg/mL, time of 3 h, and H2O2 concentration of 5%, an actual degradation efficiency of 57.5% was obtained, with 55.52% predicted by the RSM model at a 95% confidence level. Analysis of variance revealed statistical significance in the response models, with a coefficient of determination (R2) greater than 0.94, in agreement with the adjusted R2 value of less than 0.89. Kinetic analysis revealed that the degradation followed pseudo-first-order kinetics, exhibiting good reusability over multiple cycles. The study shows the potential of the UV/H2O2/Ti-MOF system as a sustainable and highly efficient approach to treating recalcitrant IS pollutants in wastewater.