Efficient Degradation of Oxytetracycline in a Novel Plug-In Three-Dimensional Photocatalytic Microreactor

The combination of a photocatalytic reaction and microfluidic technology is an increasingly popular method utilized to continuously degrade wastewater. In this work, a novel photocatalytic microreactor with TiO2 loaded on the channel center insert was designed and the photocatalytic degradation process of oxytetracycline (OTC) was investigated. Parameters such as TiO2 loading, OTC initial concentration, light intensity, and ion (NO3– and SO42–) concentrations were systematically investigated. The results show that the degradation efficiency of OTC was 56% under the optimal experimental conditions. Compared with the conventional miniaturized photocatalytic reactors, the reaction rate constant and space–time degradation efficiency of the plug-in three-dimensional photocatalytic microreactor proposed in this work were 1–2 orders of magnitude higher. In addition, dimensionless correlation was obtained to predict the degradation efficiency. This work provides a promising microfluidic technology for the process intensification of photocatalytic reaction and wastewater treatment.