Enhancement of aerobic microbial degradation of polychlorinated biphenyl in soil microcosms.
This article reports the results of various biodegradation experiments on polychlorinated biphenyl (PCB)-contaminated sandy soil employing a mixed culture of acclimatized bacteria. Following the optimization of different variables without chemical pretreatment, the elimination rate achieved of Aroclor 1242 in slurry-phase reactors was 61% after four months of treatment, with the presence of biphenyl as cosubstrate being the most important factor affecting PCB biodegradation. The biodegradation occurred as a first-order process, and it proved most effective in respect to dichlorinated biphenyls (100% removal), followed by trichlorinated (92%) and tetrachlorinated biphenyls (24%). The results also showed that the degradability of PCBs in soil may be enhanced by an advanced oxidation pretreatment (Fenton reaction), producing almost 100% elimination of PCBs at the end of the integrated chemical-biological process and 72% mineralization of the intermediates generated during the chemical pretreatment.
Manzano
Manuel A
MA
Department of Chemical Engineering and Environmental Technology, Faculty of Sea and Environmental Sciences, Cádiz University, Polígono Río San Pedro s/n, 11510 Puerto Real, Cádiz, Spain. manuel.manzano@uca.es
Perales
José A
JA
Sales
Diego
D
Quiroga
José M
JM
D000332:Aerobiosis; D001140:Aroclors / Q000737:chemistry / Q000378:metabolism; D001420:Bacteria, Aerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010084:Oxidation-Reduction; D011078:Polychlorinated Biphenyls / Q000737:chemistry / Q000378:metabolism*; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*; D013696:Temperature
D001140:Aroclors; D012987:Soil; D012989:Soil Pollutants; C027423:aroclor 1242; D002244:Carbon; D011078:Polychlorinated Biphenyls