Advances in Fluidized Bed Photocatalysis: Bridging Gaps, Standardizing Metrics, and Shaping Sustainable Solutions for Environmental Challenges

Abstract

The uncontrolled release of pollutants has led to environmental degradation and health problems. Photocatalysis has emerged as a promising technology to address environmental issues in a sustainable way. Fluidized bed reactors, in particular, offer superior photo-oxidation rates and higher mass transfer efficiency. Nonetheless, an analysis of publication trends highlights a notable gap between growing interest in photocatalysis and the limited exploitation of fluidized bed systems. In this way, this Review emphasizes the importance of standardized metrics in evaluating fluidized photocatalytic reactors, including space−time yield, photocatalytic space−time yield, specific removal rate, and electrical energy consumption per order. These metrics enable robust comparisons, highlight knowledge gaps, and spur new research to advance pollution abatement. Additionally, the Review provides insights into designing, developing, and optimizing fluidizable photocatalysis, stressing the necessity of specific physical characteristics for effective performance. The evaluation based on benchmarks showed that UV-A LEDs outperformed lamps in energy consumption and photocatalytic performance. Microreactors demonstrated high STY and PSTY values. Comparing studies solely on one benchmark may yield biased results. Researchers often overlook synergistic effects, such as photocatalyst type, irradiation source, and reactor design. Finally, combining advanced oxidative processes with photocatalysis efficiently enhanced the pollutant conversion rates.