Research on Photocatalytic Wastewater Treatment Reactors: Design, Optimization, and Evaluation Criteria

Photocatalytic wastewater treatment technology has been proposed for more than 30 years, but it is still seldom used in industry. The lack of research on high-performance and cost-effective photocatalytic wastewater treatment reactors (PWTRs) may be one of the major reasons limiting the industrial application of photocatalytic technology. To accelerate the realization of industrial application, this review emphasizes the importance of increased research on PWTRs. In this review, we analyze the role of photocatalytic technology in wastewater treatment, followed by a comprehensive discussion of PWTR design from multiple perspectives, including photocatalyst selection, loading and recovery method of photocatalysts within the reactor, light source design, and reaction conditions control. Additionally, we consider the cost of reactor design. Finally, we summarize the optimization strategy of PWTRs and the criteria for evaluating photocatalytic performance. The main innovation of this review lies in a comprehensive analysis of PWTR design, with a focus on cost-effective and high-performance solutions to promote the industrial use of photocatalytic technology.