MS title: Catalytic oxidation and removal of arsenite in the presence of Fe ions and zero-valent Al metals
Journal
Journal of Hazardous Materials
Journal Volume
317
Journal Volume
317
Pages
237-245
Start Page
237
End Page
245
ISSN
03043894
Date Issued
2016-11-05
Author(s)
Hsu, Liang-Ching
Chen, Kai-Yue
Chan, Ya-Ting
Deng, Youjun
Hwang, Che-En
Liu, Yu-Ting
Kuan, Wen-Hui
Tzou, Yu-Min
Abstract
Arsenic immobilization in acid mine drainage (AMD) is required prior to its discharge to safeguard aquatic organisms. Zero-valent aluminum (ZVAl) such as aluminum beverage cans (AlBC) was used to induce the oxidation of As(III) to As(V) and enhance the subsequent As removal from an artificially prepared AMD. While indiscernible As(III) oxidation was found in aerated ZVAl systems, the addition of 0.10-0.55 mM Fe(II) or Fe(III) into the AMD significantly promoted the As(V) production. Reactions between Fe(II) and H2O2, which was produced through an oxidative reaction of ZVAl with dissolved oxygen, generated OH radicals. Such OH radicals subsequently induced the As(III) oxidation. Over the course of the Fenton like reaction, ZVAl not only directly generated the H2O2, but indirectly enhanced the OH radical production by replenishing Fe(II). Arsenite oxidation in the aerated ZVAl/Fe and AlBC/Fe systems followed zero- and first-order kinetics. Differences in the kinetic reactions of ZVAl and AlBC with respect to As(III) oxidation were attributed to higher productive efficiency of the oxidant in the AlBC systems. After the completion of As(III) oxidation, As(V) could be removed simultaneously with Al(III) and Fe(III) by increasing solution's pH to 6 to produce Al/Fe hydroxides as As(V) scavengers or to form Al/Fe/As co-precipitates.
Subjects
Acid mine drainage
Arsenic
Hydrogen peroxide
Waste Al beverage can
Publisher
Elsevier B.V.
Type
journal article