Degradation of geosmin and 2-methylisoborneol in UV-based AOPs for photoreactors with reflective inner surfaces: Kinetics and transformation products

• Published in: Chemosphere (Oxford) 2022-11, Vol.306, p.135611-135611, Article 135611
• Main Authors: Meng, Tan, Su, Xiao, Sun, Peizhe
• Format: Article
• Language: English
• Subjects: Dynamic model; Engineering photoreactor; Geosmin; Transformation products; UV-Based advanced oxidation processes
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2022.135611

Geosmin (GSM) and 2-methylisoborneol (2-MIB) are representative musty/earthy odor compounds commonly present in surface water. In present study, the degradation of GSM and 2-MIB subject to different UV-based advanced oxidation processes (AOPs), including UV/H2O2, UV/S2O82−, UV/chlorine, and UV/chloramine, in a phosphate-buffered saline (PBS) was conducted in a photoreactor with reflective inner surfaces and compared with that in an environmental water sample. A dynamic model to predict the degradation of GSM and 2-MIB in the photoreactor with reflective inner surfaces in the four UV-based AOPs was developed applying the second-order rate constants for the GSM and 2-MIB with primary reactive species (i.e., •OH, •Cl, and •SO4−) determined in this study. The model was proven to successfully simulate the degradation of GSM and 2-MIB. In addition, 8, 7, 8, and 11 degradation intermediates were detected from UV/H2O2, UV/S2O82−, UV/chlorine, and UV/chloramine in this study, and possible degradation pathways were proposed. This study is the first to report the degradation kinetics and formation products of GSM and 2-MIB in UV/chloramine. Research based on photoreactors with reflective inner surfaces may provide some guidance for eliminating GSM and 2-MIB in UV-based AOPs for full-scale engineering applications. [Display omitted] •Various UV-based AOPs were compared in photoreactor with a reflective inner surface.•Kinetic model to simulate the degradation of GSM and 2-MIB was established.•Transformation products of GSM in UV-based AOPs were detected.•Possible degradation pathways of GSM in UV-based AOPs were proposed.•Degradation of GSM and 2-MIB were compared in PBS and environmental water sample.