title: Adsorptive removal of As(V) and As(III) from water by a Zr(IV)-loaded orange waste gel.
abstract: Orange waste, produced during juicing has been loaded with zirconium(IV) so as to examine its adsorption behavior for both As(V) and As(III) from an aquatic environment. Immobilization of zirconium onto the orange waste creates a very good adsorbent for arsenic. Adsorption kinetics of As(V) at different concentrations are well described in terms of pseudo-second-order rate equation with respect to adsorption capacity and correlation coefficients. Arsenate was strongly adsorbed in the pH range from 2 to 6, while arsenite was strongly adsorbed between pH 9 and 10. Moreover, equimolar (0.27 mM) addition of other anionic species such as chloride, carbonate, and sulfate had no influence on the adsorption of arsenate and arsenite. The maximum adsorption capacity of the Zr(IV)-loaded SOW gel was evaluated as 88 mg/g and 130 mg/g for As(V) and As(III), respectively. Column adsorption tests suggested that complete removal of arsenic was achievable at up to 120 Bed Volumes (BV) for As(V) and 8 0BV for As(III). Elution of both arsenate and arsenite was accomplished using 1 M NaOH without any leakage of the loaded zirconium. Thus this efficient and abundant bio-waste could be successfully employed for the remediation of an aquatic environment polluted with arsenic.
authors: Department of Applied Chemistry, Saga University, Honjo 1, Saga 840-8502, Japan.
authors: Biplob Kumar
authors: BK
authors: Biswas
authors: Jun-ichi
authors: J
authors: Inoue
authors: Katsutoshi
authors: K
authors: Inoue
authors: Kedar Nath
authors: KN
authors: Ghimire
authors: Hiroyuki
authors: H
authors: Harada
authors: Keisuke
authors: K
authors: Ohto
authors: Hidetaka
authors: H
authors: Kawakita
mesh_terms: D000327:Adsorption; D001149:Arsenates / Q000737:chemistry*; D018053:Arsenites / Q000737:chemistry*; D001628:Beverages; D032084:Citrus sinensis; D019649:Food Industry; D005782:Gels; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007700:Kinetics; D008906:Mining; D014866:Waste Products; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*; D014881:Water Supply; D015040:Zirconium / Q000737:chemistry*
chemical_list: D001149:Arsenates; D018053:Arsenites; D005782:Gels; D007220:Industrial Waste; D014866:Waste Products; D014874:Water Pollutants, Chemical; D015040:Zirconium; C015001:arsenite; C025657:arsenic acid