Box–Behnken Experimental Design for the Removal of Chemical Oxygen Demand in Food Processing Wastewater by Hybrid Titania‐Based Composite

ABSTRACT A hybrid composite of titania, alumina, and carbon nanotubes (TiO 2 /Al 2 O 3 /CNT) was synthesized and applied as a photocatalyst for the degradation of organic pollutants in sauce processing wastewater. The structural, morphological, and surface properties of the composite were characterized using Fourier‐transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area analysis, and X‐ray diffraction (XRD). Photocatalytic performance was evaluated under ultraviolet light‐emitting diode (UV‐LED) irradiation. Key operational parameters, namely catalyst dosage, irradiation time, and solution pH, were optimized using a Box–Behnken design (BBD). The resulting quadratic models exhibited high predictive accuracy ( R 2 > 0.986), and under optimized conditions, chemical oxygen demand (COD) removal reached up to 75%. Kinetic analysis confirmed that the ternary TiO 2 ‐based composite outperformed both binary and single‐phase systems, highlighting its potential as an effective photocatalyst for treating industrial organic wastewater.