title: Facile synthesis of highly active hydrated yttrium oxide towards arsenate adsorption.
abstract: A novel hydrated yttrium oxide adsorbent with high capacity towards the arsenate (As(V)) adsorption was fabricated by a one-step hydrothermal process. Structure analysis identified the hydrated yttrium oxide to be Y2O(OH)4·1.5H2O, which displayed as irregular rods in the range of tens to hundreds of nanometers. The adsorbent exhibited favorable As(V) adsorption efficiency in a wide pH range from 4.0 to 7.0, with the maximum adsorption capacity of 480.2mg-As/g obtained at pH 5.0. Both the kinetics and isotherm studies demonstrated that the adsorption of the As(V) was a monolayer chemical adsorption process, in which the ion exchange between the hydroxyl groups on the hydrated yttrium oxide and arsenate anions played a key role in the uptake of the As(V). During the adsorption, the As(V) anions were replaced the hydroxyl groups and bound to the hydrated yttrium oxide via the linkage of AsOY. The presence of fluoride and phosphate greatly hindered the As(V) uptake on the hydrated yttrium oxide, whereas the bicarbonate, sulfate and humic acid showed insignificant impacts on the removal.
authors.affiliation: Department of Civil and Environmental Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Department of Civil and Environmental Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore.
authors.forename: Ling
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Chemical Engineering, Hefei University of Technology, Hefei 230009, China.
authors.forename: Min
authors.initials: M
authors.lastname: Sun
authors.affiliation: Department of Civil and Environmental Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore. Electronic address: paulchen@nus.edu.sg.
authors.forename: J
authors.initials: J
authors.lastname: Paul Chen
keywords: Adsorption; Arsenate; Hydrated yttrium oxide adsorbent; Hydrothermal process