title: Simulation of bioremediation of chlorophenols in a sandy aquifer.
abstract: Bioremediation of consecutive spills of phenol, 2-chlorophenol (2-MCP), 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlororphenol as single pollutants was investigated in eight pilot plant scale sand columns system (100 cm l, 6 cm ID), simulating the conditions, which could be created in the saturated zone of a pristine aquifer following an accidental spill. Bioremediation in this study consisted of re-circulating local groundwater through the polluted site in a controlled manner following a closed-loop configuration. Intrinsic microbial development was enhanced by adding the necessary nutrients. Consecutive accidental spills of 480-mg phenol/kg soil; 140-mg 2-MCP/kg; 14-mg 2,4,6-TCP/kg soil and 17-mg pentachlorophenol (PCP)/kg soil under saturated conditions and a continuous specific discharge of 0.56 cm min(-1) were simulated. Degradation curves demonstrated first-order kinetics. Biodegradation rates (k1) were influenced by consecutive exposures. Calculated rate constants for biodegradation for sole substrate experiments were in the range of 0.06-0.15 day(-1), 0.21-1.20 day(-1), 0.04-2.28 day(-1) and 0.01-0.03 day(-1) for phenol, 2-MCP, 2,4,6-TCP and PCP, respectively. The acclimation of the aquifer to simulated consecutive accidental spills was found to be directly proportional to the cumulative load of each single chlorophenol. A relationship between the octanol water partitioning (Kow) values and the experimental degradation rates (k1) was found.
authors.affiliation: Division of Environmental and Water Resources Engineering, Faculty of Civil Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel. blanca@tx.technion.ac.il
authors.forename: B
authors.initials: B
authors.lastname: Antizar-Ladislao
authors.forename: N I
authors.initials: NI
authors.lastname: Galil
mesh_terms: D001673:Biodegradation, Environmental; D002733:Chlorophenols / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008962:Models, Theoretical; D000442:Octanols / Q000737:chemistry; D012822:Silicon Dioxide; D012995:Solubility; D014881:Water Supply
chemical_list: D002733:Chlorophenols; D000442:Octanols; D012822:Silicon Dioxide