Visible-Light-Driven Photocatalytic Degradation of Organic Water Pollutants Promoted by Sulfite Addition

Wei Deng, Huilei Zhao, Fuping Pan, Xuhui Feng, Bahngmi Jung, Ahmed Abdel-Wahab, Bill Batchelor, Ying Li

Research output: Contribution to journalArticle

57 Citations (Scopus)

Abstract

Solar-driven heterogeneous photocatalysis has been widely studied as a promising technique for degradation of organic pollutants in wastewater. Herein, we have developed a sulfite-enhanced visible-light-driven photodegradation process using BiOBr/methyl orange (MO) as the model photocatalyst/pollutant system. We found that the degradation rate of MO was greatly enhanced by sulfite, and the enhancement increased with the concentration of sulfite. The degradation rate constant was improved by 29 times in the presence of 20 mM sulfite. Studies using hole scavengers suggest that sulfite radicals generated by the reactions of sulfite (sulfite anions or bisulfite anions) with holes or hydroxyl radicals are the active species for MO photodegradation using BiOBr under visible light. In addition to the BiOBr/MO system, the sulfite-assisted photocatalysis approach has been successfully demonstrated in BiOBr/rhodamine B (RhB), BiOBr/phenol, BiOI/MO, and Bi2O3/MO systems under visible light irradiation, as well as in TiO2/MO system under simulated sunlight irradiation. The developed method implies the potential of introducing external active species to improve photodegradation of organic pollutants and the beneficial use of air pollutants for the removal of water pollutants since sulfite is a waste from flue gas desulfurization process.

Original languageEnglish
Pages (from-to)13372-13379
Number of pages8
JournalEnvironmental Science and Technology
Volume51
Issue number22
DOIs
Publication statusPublished - 21 Nov 2017

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ASJC Scopus subject areas

  • Chemistry(all)
  • Environmental Chemistry

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