title: Degradation of off-gas toluene in continuous pyrite Fenton system.
abstract: Degradation of off-gas toluene from a toluene reservoir and a soil vapor extraction (SVE) process was investigated in a continuous pyrite Fenton system. The removal of off-gas toluene from the toluene reservoir was >95% by 8h in the pyrite Fenton system, while it was ∼97 % by 3h in classic Fenton system and then rapidly decreased to initial level by 8h. Continuous consumption of low Fe(II) concentration dissolved from pyrite surface (0.05-0.11 mM) was observed in the pyrite Fenton system, which can lead to the effective and successful removal of the gas-phase toluene due to stable production of OH radical (OH). Inhibitor and spectroscopic test results showed that OH was a dominant radical that degraded gas-phase toluene during the reaction. Off-gas toluene from the SVE process was removed by 96% in the pyrite Fenton system, and remnant toluene from rebounding effect was treated by 99%. Main transformation products from toluene oxidation were benzoic acid (31.4%) and CO2 (38.8%) at 4h, while traces of benzyl alcohol (1.3%) and benzaldehyde (0.7%) were observed. Maximum operation time of continuous pyrite Fenton system was estimated to be 56-61 d and its optimal operation time achieving emission standard was 28.9 d.
authors.affiliation: Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Kyunghoon
authors.initials: K
authors.lastname: Choi
authors.affiliation: Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Sungjun
authors.initials: S
authors.lastname: Bae
authors.affiliation: Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea. Electronic address: woojin_lee@kaist.ac.kr.
authors.forename: Woojin
authors.initials: W
authors.lastname: Lee
mesh_terms: D000397:Air Pollution / Q000517:prevention & control; D004785:Environmental Pollutants / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D010084:Oxidation-Reduction; D013440:Sulfides / Q000737:chemistry*; D014050:Toluene / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000737:chemistry
chemical_list: D004785:Environmental Pollutants; C045076:Fenton's reagent; D013440:Sulfides; D055549:Volatile Organic Compounds; C011342:pyrite; D014050:Toluene; D006861:Hydrogen Peroxide; D007501:Iron
keywords: Continuous pyrite Fenton; OH; Off-gas organic contaminant; Soil vapor extraction; Toluene