Photocatalytically-assisted oxidative adsorption of As(III) using sustainable multifunctional composite material - Cu2O doped anion exchanger

Irena Jacukowicz-Sobala; Agnieszka Ciechanowska; Elżbieta Kociołek-Balawejder; Anna Gibas; Adrian Zakrzewski

doi:10.1016/j.jhazmat.2022.128529

Photocatalytically-assisted oxidative adsorption of As(III) using sustainable multifunctional composite material - Cu₂O doped anion exchanger

J Hazard Mater. 2022 Jun 5:431:128529. doi: 10.1016/j.jhazmat.2022.128529. Epub 2022 Feb 21.

Authors

Irena Jacukowicz-Sobala¹, Agnieszka Ciechanowska², Elżbieta Kociołek-Balawejder², Anna Gibas³, Adrian Zakrzewski⁴

Affiliations

¹ Department of Chemical Technology, Wroclaw University of Economics and Business, 118/120 Komandorska St., 53-345 Wrocław, Poland. Electronic address: irena.jacukowicz@ue.wroc.pl.
² Department of Chemical Technology, Wroclaw University of Economics and Business, 118/120 Komandorska St., 53-345 Wrocław, Poland.
³ Department of Mechanics, Materials and Biomedical Engineering, Wroclaw University of Science and Technology, 25 M Smoluchowskiego St., 50-370 Wrocław, Poland.
⁴ Department of Mechanical Engineering, Wroclaw University of Science and Technology, 5 Łukasiewicza St., 50-371 Wrocław, Poland.

PMID: 35220119
DOI: 10.1016/j.jhazmat.2022.128529

Abstract

The purpose of the presented study was to explore the photocatalytic activity of Cu₂O-supported anion exchangers and to explain the mechanism of their action in water purification processes. The functionality of this type of material was studied in the process of As(III) removal from water. As a result of the reactivity of cuprous oxide and functional groups of the polymer, the obtained composite exhibited complex activity towards arsenic(III) species. The adsorption studies were conducted under various conditions: dark, UV-VIS irradiation, VIS irradiation, under aerobic and anoxic conditions. The results from chemical analyses were supported by instrumental analyses - X-ray photoelectron spectroscopy, and FTIR and Raman spectroscopy. These studies showed that the mechanism of As(III) oxidative adsorption is based on the coupling of several reaction pathways: 1) photocatalytic oxidation involving Cu₂O as a photocatalyst, and photogenerated holes and ROS as oxidative agents, 2) chemical oxidation on the surface of CuO (being a result of the ageing process) with a re-oxidation of the produced Cu₂O to CuO by ROS and oxygen present in water, and 3) photochemical oxidation of As(III) in solution under UV light irradiation and subsequent adsorption of arsenates in the functional groups of the polymer.

Keywords: As(III) oxidative adsorption; As(III) photocatalytic oxidation; Cuprous oxide; Hybrid anion exchanger.