title: Toluene biodegradation in a solid/liquid system involving immobilized activated sludge and silicone oil as pollutant reservoir.
abstract: A solid/liquid system involving activated sludge immobilized in an agar medium and a non-aqueous phase liquid containing the target pollutant has been considered to treat a model hydrophobic volatile organic compound, toluene. The positive impact of the use of a multiphase bioreactor is that the organic phase constitutes a pollutant reservoir and also helps to overcome possible pollutant toxicity. In addition and to overcome the drawbacks of the use of a solid organic phase (high pressure drop and low mass transfer) instead of a liquid organic phase, the considered solid phase was the aqueous. Consequently, silicone oil (polydimethylsiloxane) which showed its relevance for implementation in multiphase bioreactors was used. Promising results were observed from the analysis of toluene in the gaseous phase; for an initial amount of 2 g L(-1) related to the organic phase, a v/v ratio of 0.5 of the organic phase to the aqueous agar phase, total toluene consumption was observed in about 9 days, leading to a global biodegradation rate of approximately 3.1 mg L(-1) h(-1), namely in the range of values previously observed in liquid/liquid systems.
authors.affiliation: a École Nationale Supérieure de Chimie de Rennes, CNRS , UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 , France.
authors.forename: Manuel
authors.initials: M
authors.lastname: Diz Castro
authors.forename: Diego
authors.initials: D
authors.lastname: Gómez-Díaz
authors.forename: Abdeltif
authors.initials: A
authors.lastname: Amrane
authors.forename: Annabelle
authors.initials: A
authors.lastname: Couvert
mesh_terms: D000393:Air Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D001673:Biodegradation, Environmental; D052918:Environmental Restoration and Remediation / Q000379:methods; D044367:Phase Transition; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology*; D012827:Silicone Oils / Q000737:chemistry*; D014050:Toluene / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D000393:Air Pollutants; D012722:Sewage; D012827:Silicone Oils; D014050:Toluene
keywords: activated sludge; immobilized culture; silicone oil; toluene; two-phase partitioning bioreactor