title: Hydrocarbon removal from bilgewater by a combination of air-stripping and photocatalysis.
abstract: In order to prevent hydrocarbon discharge at sea from the bilge of ships, the International Maritime Organization (IMO) enacted the MARPOL 73/78 convention in which effluents are now limited to those with maximum oil content of 15 ppmv. Thus, photocatalysis and air-stripping were combined for the hydrocarbon removal from a real oily bilgewater sample and an original monitoring of both aqueous and gaseous phases was performed by GC/MS to better understand the process. Our results show that the hydrocarbon oil index [HC] can be reduced to its maximum permissible value of 15 ppmv (MARPOL) in only 8.5h when photocatalysis and air-stripping are used together in a synergistic way, as against 17 h when photocatalysis is used alone. However, this air-assisted photocatalytic process emits a large quantity of volatile organic compounds (VOC) and, within the first four hours, ca. 10% of the hydrocarbon removal in the aqueous phase is actually just transferred into the gaseous one. Finally, we highlight that the n-alkanes with a number of carbon atoms higher than 15 (N(C)>15) are those which most decrease the rate of [HC] removal.
authors.affiliation: University Lyon 1, Lyon, F-69626, France, CNRS, UMR5256, IRCELYON, Institut de Recherches sur la Catalyse et l'Environnement de Lyon, Villeurbanne, F-69626, France. david.cazoir@ircelyon.univ-lyon1.fr
authors.forename: D
authors.initials: D
authors.lastname: Cazoir
authors.forename: L
authors.initials: L
authors.lastname: Fine
authors.forename: C
authors.initials: C
authors.lastname: Ferronato
authors.forename: J-M
authors.initials: JM
authors.lastname: Chovelon
mesh_terms: D000388:Air; D000393:Air Pollutants / Q000032:analysis; D002384:Catalysis; D006838:Hydrocarbons / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects; D010100:Oxygen / Q000737:chemistry; D055668:Photochemical Processes; D012767:Ships; D014466:Ultraviolet Rays; D055549:Volatile Organic Compounds / Q000032:analysis; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000032:analysis / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D000393:Air Pollutants; D006838:Hydrocarbons; D010100:Oxygen; D055549:Volatile Organic Compounds; D062065:Wastewater; D014874:Water Pollutants, Chemical