A Comprehensive Review of Photochemical Degradation: An Advanced Oxidation Process for the Decomposition and Mineralization of BTEX Compounds in Gas Phase

Background: BTEX compounds are the most significant VOCs due to their carcinogenic potential and severe adverse effects on human health and the environment. Their removal from polluted air is therefore essential. The present study aimed to review and compare photocatalytic methods for removing BTEX compounds from air. Methods: A comprehensive review was conducted by searching databases on Scopus, ScienceDirect, EBSCO, RSC, and PubMed from 2013 to 2024. A total of 245 articles were found, and 52 were finally reviewed, covering variables such as BTEX analysis methods, photocatalytic processes for their removal, their advantages and disadvantages, and the parameters affecting these processes. Results: According to the findings, non-destructive methods are not suitable for air pollution control because they cannot eliminate pollutants and rely solely on transport to remove them. Destructive methods such as thermal oxidation offer higher degradation efficiency (up to 95%), but are associated with high energy consumption and formation of by-products. Photocatalytic degradation has emerged as a promising, environmentally friendly, and energy-efficient approach for VOC removal. The use of semiconductor nanoparticles such as TiO₂, ZnO, and V₂O₅, along with modifications to the visible light absorption range, reduction in energy demand and regeneration, enhancement of photocatalyst stability, and increased degradation efficiency (up to 99%). Conclusion: Finally, the energy consumption and environmental compatibility evaluation confirmed that the doped photocatalysts not only offer superior performance but also comply well with the principles of green chemistry and sustainable environmental practices management.