title: Treatment of groundwater contaminated with gasoline components by an ozone/UV process.
abstract: In this paper, the treatment of real groundwater samples contaminated with gasoline components, such as benzene, toluene, ethylbenzene, and xylene (BTEX), methyl tert-butyl ether (MTBE), tert-butyl alcohol (TBA), and other gasoline constituents in terms of total petroleum hydrocarbons as gasoline (TPHg) by an ozone/UV process was investigated. The treatment was conducted in a semi-batch reactor under different experimental conditions by varying ozone gas dosage and incident UV light intensity. The groundwater samples contained BTEX compounds, MTBE, TBA, and TPHg in the ranges of 5-10000, 3000-5500, 80-1400, and 2400-20000 microgl(-1), respectively. The ozone/UV process was very effective compared to ozonation in the removal of the gasoline components from the groundwater samples. For the various gasoline constituents, more than 99% removal efficiency was achieved for the ozone/UV process and the removal efficiency for ozonation was as low as 27%. The net ozone consumed per mol of organic carbon (from BTEX, MTBE, and TBA) oxidized varied in the range of 5-60 for different types of groundwater samples treated by the ozone/UV process. In ozonation experiments, it was observed that the presence of sufficient amount of iron in groundwater samples improved the removal of BTEX, MTBE, TBA, and TPHg.
authors.affiliation: Department of Civil, Construction, and Environmental Engineering, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, United States. tgaroma@mail.sdsu.edu
authors.forename: Temesgen
authors.initials: T
authors.lastname: Garoma
authors.forename: Mirat D
authors.initials: MD
authors.lastname: Gurol
authors.forename: Olufisayo
authors.initials: O
authors.lastname: Osibodu
authors.forename: Lalitha
authors.initials: L
authors.lastname: Thotakura
mesh_terms: D001554:Benzene / Q000737:chemistry / Q000302:isolation & purification; D001555:Benzene Derivatives / Q000737:chemistry / Q000302:isolation & purification; D002274:Carcinogens, Environmental / Q000737:chemistry / Q000302:isolation & purification*; D005742:Gasoline; D008738:Methyl Ethers / Q000737:chemistry / Q000302:isolation & purification; D010126:Ozone / Q000737:chemistry*; D014050:Toluene / Q000737:chemistry / Q000302:isolation & purification; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*; D014992:Xylenes / Q000737:chemistry / Q000302:isolation & purification; D020002:tert-Butyl Alcohol / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D001555:Benzene Derivatives; D002274:Carcinogens, Environmental; D005742:Gasoline; D008738:Methyl Ethers; D014874:Water Pollutants, Chemical; D014992:Xylenes; C043243:methyl tert-butyl ether; D014050:Toluene; D010126:Ozone; D001554:Benzene; C004912:ethylbenzene; D020002:tert-Butyl Alcohol