title: Self-flocculated powdered activated carbon with different oxidation methods and their influence on adsorption behavior.
abstract: The commercial powdered activated carbon (PAC) has been selectively oxidized by two methods. The two oxidized methods are wet oxidation with ammonium persulfate and thermal treatment after acidification with hydrochloride acid, respectively. The two oxidized PAC were then functionalized with thermoresponsive poly (N-isopropylacrylamide) (PNIPAM) in aqueous solution at ambient temperature. Comparing the two oxidized PAC products and their grafted derivatives, the oxidized PAC modified with thermal treatment after acidification shows larger surface area of 1184 m(2)/g and better adsorption of bisphenol A. Its derivative also exhibits relatively large surface area and adsorption capacity after grafted with PNIPAM. The maximum surface adsorption capacity simulated under Langmuir Models reached 156 mg/g. In addition, the grafted PAC products show self-flocculation behaviors with rapid response to temperature because of the thermal phase transition and entanglement behaviors of PNIPAM. The present study provides a new way to obtain carboxyl-rich activated carbon with large surface area and better adsorption capacity. The retrievable grafted PAC with good self-flocculation effect responsive to temperature will have high potential application in water remediation which requires pre-heating and emergency water treatment in the wild.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Heilongjiang Province, Harbin 150001, China.
authors.forename: Zailin
authors.initials: Z
authors.lastname: Gong
authors.affiliation: College of Chemistry, Liaoning University, Liaoning Province, Shenyang 110000, China.
authors.forename: Shujin
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Heilongjiang Province, Harbin 150001, China. Electronic address: majunhit@126.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: College of Chemistry, Liaoning University, Liaoning Province, Shenyang 110000, China. Electronic address: xd623@sina.com.
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Zhang
keywords: Adsorption; Oxidation; Poly(N-isopropylacrylamide); Powdered activated carbon; Self-flocculation