title: Competitive sorption behavior of copper(II) and herbicide propisochlor on humic acids.
abstract: The competitive sorption behavior of Cu2+ and propisochlor on humic acids (HA) was investigated using a batch method. The sorption equilibrium time of propisochlor on HA was 12 h when its initial concentration was 4 or 10 mg L(-1). The results showed that the Langmuir model can best describe the sorption behavior of propisochlor on HA. The added Cu2+ reduced the solid-phase concentration of propisochlor on HA, and the Langmuir model can also describe the sorption behavior of propisochlor on HA when the Cu2+ concentration is 100 and 200 mg L(-1). The sorption of propisochlor on HA did not remarkably affect the sorption of Cu2+ on HA when the concentration of propisochlor was below 20 mg L(-1). Cu2+ may compete with propisochlor for the sorption sites of HA, such as carboxylic and phenolic groups. It can be concluded that Cu2+ fast adsorbed to the HA matrix, altered its physical and chemical properties, and thus decreased the solid-phase concentrations of propisochlor on HA. In natural water, Cu2+ may promote the release of propisochlor from HA, and thus affect its transport, transformation, and fate in the environment.
authors.affiliation: Department of Soil Pollution Control, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Zhonghou
authors.initials: Z
authors.lastname: Xu
authors.forename: Manxiang
authors.initials: M
authors.lastname: Huang
authors.forename: Qingbao
authors.initials: Q
authors.lastname: Gu
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Yunzhe
authors.initials: Y
authors.lastname: Cao
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Du
authors.forename: Duanping
authors.initials: D
authors.lastname: Xu
authors.forename: Qing
authors.initials: Q
authors.lastname: Huang
authors.forename: Fasheng
authors.initials: F
authors.lastname: Li
mesh_terms: D000081:Acetamides / Q000737:chemistry*; D000327:Adsorption; D001667:Binding, Competitive; D003300:Copper / Q000737:chemistry*; D006812:Humic Substances; D008956:Models, Chemical; D015394:Molecular Structure
chemical_list: D000081:Acetamides; D006812:Humic Substances; D003300:Copper; C470819:propisochlor