Fast Aqueous Biodegradation of Highly-Volatile Organic Compounds in a Novel Anaerobic Reaction Setup

Identifier:  imarina:4171117

Handle: https://hdl.handle.net/20.500.11797/imarina4171117

Authors:  Garcia-Martinez, Yonhara; Chirinos, Judith; Bengoa, Christophe; Stuber, Frank; Font, Josep; Fortuny, Agusti; Fabregat, Azael

Abstract:
The present work explores the biodegradation of some emerging pollutants (EPs) in an anaerobic slowly-agitated up-flow packed-bed reactor (USPBR) filled with biological activated carbon (BAC). Chlorobenzene (CB) and 2,4-dichlorophenoxyacetic acid (2,4-D) were selected as volatile organic compounds (VOC) and major constituents of many pesticides. Experiments carried out in continuous operation showed that bioconversion up to 90% was achieved for CB and 2,4-D, at space times below 0.6 h and 1.2 h, respectively, at ambient temperature. Overall, removal rates of 0.89 g L-1 d(-1) and 0.46 g L-1 d(-1) were obtained for CB and 2,4-D, respectively. These results revealed that the degradation of CB and 2,4-D in this anaerobic configuration of bioreactor is an efficient and fast process. The Michaelis-Menten model properly describes the degradation process for CB. Above initial concentrations of 100 mg L-1, 2,4-D presented a considerable inhibitory effect over the biofilm. For this reason, a substrate inhibition factor was included in the Michaelis-Menten equation; the expanded model presented a good fitting to the experimental data, regardless of the inlet concentration. Therefore, USPBR-BAC combination showed to be a highly efficient system for the biodegradation of such compounds.