title: Kinetics of biological perchlorate reduction and pH effect.
abstract: Batch experiments were conducted to investigate the kinetics of perchlorate reduction by heterotrophic and mixed perchlorate-reducing bacteria. Substrate-utilizing and cellular maintenance models were employed to fit the experimental data for microbial perchlorate reduction. The half saturation constant, K(s), obtained in this study was below 0.1mg/L, which indicated that perchlorate-reducing bacteria are effective at utilizing low concentrations of perchlorate. The effect of pH on the kinetics of microbial perchlorate reduction was also studied. Perchlorate reduction occurred throughout the pH range from 5.0 to 9.0. Nevertheless, the rates of perchlorate removal by a unit mass of bacteria were significantly different at various pHs with a maximum rate at pH 7.0. The variation of q(max) with pH was described well with a Gaussian peak equation. This equation is expected to be applicable for practical purposes when pH effects need to be considered.
authors.affiliation: Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, USA.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
authors.forename: Lee
authors.initials: L
authors.lastname: Lippincott
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Meng
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010084:Oxidation-Reduction; D010472:Perchlorates / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification / Q000379:methods
chemical_list: D010472:Perchlorates; D012722:Sewage; D014874:Water Pollutants, Chemical; C494474:perchlorate