Absorption and biodegradation of toluene: Optimization of its initial concentration and the biodegradable non-aqueous phase liquid volume fraction

Imane Béchohra (1, 2) , Annabelle Couvert (1, 2) , Abdeltif Amrane (2, 1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 UEB - Université européenne de Bretagne - European University of Brittany

Di (2-EthylHexyl) Phthalate (DEHP) was selected as a biodegradable organic solvent to be implemented in a two-phase partitioning bioreactor (TPPB) dedicated to remove a model hydrophobic volatile organic compound (VOC), toluene. In a first step, the absorption capacity of toluene in the selected organic solvent was examined according to the partition coefficients H. In a second step, toluene biodegradation in DEHP by non-acclimated activated sludge was carried out for different volume fractions of DEHP in water and five different toluene concentrations (4.3, 43, 106, 212 and 430 mg l−1). Toluene showed high affinity for DEHP with H = 0.99 Pa m3 mole−1. Both toluene and DEHP were completely consumed for 4.3 mg l−1 (initial toluene concentration) and a volume ratio of 0.1% DEHP in water. For an initial toluene concentration of 106 mg l−1 and a volume ratio of 0.1%, total toluene consumption and 87% DEHP degradation yield were obtained after seven days of incubation.

Keywords: Activated sludge; Biodegradation; DEHP; VOC

Domains: Chemical Sciences

Imane Béchohra, Annabelle Couvert, Abdeltif Amrane. Absorption and biodegradation of toluene: Optimization of its initial concentration and the biodegradable non-aqueous phase liquid volume fraction. International Biodeterioration and Biodegradation, 2015, 104, pp.350--355. ⟨10.1016/j.ibiod.2015.07.004⟩. ⟨hal-01188192⟩