title: Adsorption and desorption of atrazine on carbon nanotubes.
abstract: The potential impact of carbon nanotubes (CNTs) on human health and the environment is receiving more and more attention. The high surface area of CNTs tends to adsorb a large variety of toxic chemicals, which may enhance the toxicity of CNTs and/or toxic chemicals. In this study, adsorption and desorption of atrazine on carbon nanotubes from aqueous solution were studied through batch reactors. The adsorption equilibrium isotherms were nonlinear and were fitted by Freundlich, Langmuir, and Polanyi-Manes models. It was found that the Polanyi-Manes model described the adsorption process better than other two isotherm models. Together with the "characteristic curve," the Polanyi adsorption potential theory is applicable to describe the adsorption process of atrazine on CNTs. Thermodynamic calculations indicated that the adsorption reaction of atrazine on CNTs is spontaneous and exothermic. The desorption data showed that no significant desorption hysteresis occurred. High adsorption capacity and adsorption reversibility of atrazine on CNTs suggest that CNTs have high health and environmental risks, whereas they have potential applications for atrazine removal from water.
authors.affiliation: State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, POB 2871, Beijing 10085, PR China. yanxmin@163.com
authors.forename: X M
authors.initials: XM
authors.lastname: Yan
authors.forename: B Y
authors.initials: BY
authors.lastname: Shi
authors.forename: J J
authors.initials: JJ
authors.lastname: Lu
authors.forename: C H
authors.initials: CH
authors.lastname: Feng
authors.forename: D S
authors.initials: DS
authors.lastname: Wang
authors.forename: H X
authors.initials: HX
authors.lastname: Tang
mesh_terms: D000327:Adsorption; D001280:Atrazine / Q000737:chemistry* / Q000633:toxicity; D008956:Models, Chemical; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000633:toxicity; D018508:Water Purification
chemical_list: D037742:Nanotubes, Carbon; D014874:Water Pollutants, Chemical; D001280:Atrazine