title: Sonochemical desorption and destruction of 4-chlorobiphenyl from synthetic sediments.
abstract: The application of ultrasound for the treatment of polychlorinated biphenyl (PCB) contaminated sediments was explored in this study with a model system of 4-chlorobiphenyl (4-CB) and synthetic sediments. In the presence of an ultrasonic probe, operating at 20 kHz with a power density of 460 W L(-1), more than 90% of 4-CB in aqueous homogeneous solution was destroyed after 20 min, with an apparent first-order rate constant, k, of 0.120 min(-1). In addition, experiments investigating the destruction of dissolved 4-CB in the presence of bare silica or alumina particles or dissolved humic acid (HA) had lower degradation rates than in aqueous homogeneous solutions. Increasing the bare particle concentration or dissolved HA concentration further lowered the degradation rate. However, in investigating the desorption and destruction of sorbed 4-CB from humic acid laden alumina particles, the effect of particles and released dissolved HA on the degradation rate are simply additive, and desorption of 4-CB does not appear to further complicate the system. A kinetic analysis of the system revealed that desorption of 4-CB from particles was not a limiting factor in this system.
authors.affiliation: Department of Civil and Environmental Engineering and Geodetic Science, The Ohio State University, Columbus 43210, USA.
authors.forename: Yifang
authors.initials: Y
authors.lastname: Lu
authors.forename: Linda K
authors.initials: LK
authors.lastname: Weavers
mesh_terms: D000327:Adsorption; D001713:Biphenyl Compounds / Q000032:analysis / Q000737:chemistry*; D004785:Environmental Pollutants / Q000032:analysis*; D004787:Environmental Pollution / Q000517:prevention & control*; D019015:Geologic Sediments / Q000737:chemistry*; D007700:Kinetics; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000737:chemistry*; D014465:Ultrasonics
chemical_list: D001713:Biphenyl Compounds; D004785:Environmental Pollutants; D011078:Polychlorinated Biphenyls; C006983:4-chlorobiphenyl