A Two-Level Factorial Design for calcium cobaltite doped scandium /chitosan films Composite in pharmaceutical wastewater photocatalytic degradation

The photocatalytic decomposition rates of a widely used nonsteroidal anti-inflammatory drug naproxen wastewater were assessed using Ca ₃ Co ₄ O ₉ and Sc-doped Ca ₃ Co ₄ O ₉ /Chitosan nanocomposit films as photocatalyst irradiating with visible light. Chitosan was extracted from shrimp shells as an immobilization matrix for the prepared photocatalyst. The Ca ₃ Co ₄ O ₉ and Sc-doped Ca ₃ Co ₄ O ₉ photocatalyst was synthesized using the Pechini method and the prepared composites were characterized using FTIR, XRD, TEM and optical properties. Naproxen was chosen as a model compound for pharmaceutical wastewater to determine the photocatalytic performance of the prepared nanocomposite films. The % naproxen removal attained 95% using chitosan _/ Ca ₃ Co _3.99 Sc _0.01 O ₉ , the photodegradation followed pseudo-first-order kinetics. To gain an extensive comprehension of the photodegradation process, the key active species involving the (50/50) chitosan/ Ca ₃ Co _3.99 Sc _0.01 O ₉ nanocomposite films were also investigated. Various scavengers were incorporated into the naproxen degradation process to block potential superoxide radicals ( \(\:{O}_{2}^{\cdot\:}\)), photoexcited holes (h ⁺ ), and hydroxyl radicals (⋅OH) to fulfill this target. Removal of COD, BOD, and TOC in real pharmaceutical wastewater samples exceeded 85%. Even after five cycles, the film's reusable properties demonstrated continuous photocatalytic capabilities, with only a 10% loss. The investigation utilized a two-level factorial design that included diagnostic plots such as the perturbations plot, ANOVA, and Pareto's chart.