title: Fe(0)-Fe3O4 nanocomposites embedded polyvinyl alcohol/sodium alginate beads for chromium (VI) removal.
abstract: In this study, Fe(0)-Fe3O4 nanocomposites embedded polyvinyl alcohol (PVA)/sodium alginate (SA) beads were synthesized, which exhibited an excellent physical properties and catalytic reactivity, and a robust performance of post-separation (complete separation using a simple grille) and reusability (efficiency of 69.8% after four runs) in Cr(VI) removal. 5.0 wt% PVA with 1.5 wt% SA was the optimal proportion for beads molding, and the followed acidification and reduction treatments were critical to ensure high mechanical strength and high Cr(VI) removal ability of beads. Effects of Fe(0) and Fe3O4 mass fraction, initial pH and Cr(VI) concentration on final removal efficiency were also evaluated. Merely 0.075 wt% Fe(0) together with 0.30 wt% Fe3O4 was sufficient to deal with 20 mg L(-1) Cr(VI) solution. The efficiency decreased from 100 to 79.5% as initial Cr(VI) increased from 5 to 40 mg L(-1), while from 99.3 to 76.3% with increasing pH from 3.0 to 11.0. This work provides a practical and high-efficient method for heavy metal removal from water body, and simultaneously solves the problems in stabilization, separation and regeneration of Fe(0) nanoparticles.
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Xiaoshu
authors.initials: X
authors.lastname: Lv
authors.forename: Guangming
authors.initials: G
authors.lastname: Jiang
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Xue
authors.forename: Donglei
authors.initials: D
authors.lastname: Wu
authors.forename: Tiantian
authors.initials: T
authors.lastname: Sheng
authors.forename: Chen
authors.initials: C
authors.lastname: Sun
authors.forename: Xinhua
authors.initials: X
authors.lastname: Xu
mesh_terms: D000327:Adsorption; D000464:Alginates / Q000737:chemistry; D002857:Chromium / Q000737:chemistry*; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D011142:Polyvinyl Alcohol / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D014874:Water Pollutants, Chemical; D002857:Chromium; D020723:Glucuronic Acid; D011142:Polyvinyl Alcohol; D007501:Iron; D052203:Ferrosoferric Oxide
keywords: Acidification; Cr(VI) removal; Fe(0)-Fe(3)O(4) nanocomposites; Immobilization; Polyvinyl alcohol/sodium alginate beads