Optimization of TiO₂/ACF Photocatalytic Continuous Treatment of MB Wastewater Based on Response Surface Methodology

While high-efficiency photocatalysts have been extensively researched, there is still a scarcity of reports focusing on enhancing the practical application conditions of low-cost engineering photocatalysts. In this study, a 13.8-L continuous streamer catalytic reactor was developed utilizing low-cost self-made TiO₂/ACF photocatalyst. Employing the Box-Behnke response surface method, the study assessed the reactor’s efficiency in treating organic wastewater using methylene blue (MB) as the model pollutant. The TiO₂/ACF photocatalysis was characterized by XRD, EDS, and SEM, and the results showed that the nano-TiO₂ was uniformly loaded with the surface of activated carbon fibers in a lamellar form. Results indicated that with a single cycle time of 134 min and a catalyst amount of 95 cm × 95 cm, the average decolorization rate for 3 mg/L MB wastewater was 90.63%, following quasi-second-order kinetics. The MB wastewater’s decolorization efficiency swiftly reached 89.8% within the initial 120 min, maintaining around 90% during continuous 600-min treatment. The optimal catalyst condition was identified, enhancing photodegradation efficiency of MB organic molecules. The developed photocatalytic equipment exhibited high efficiency and stability in degrading low-concentration organic molecules.