Simultaneous oxidation and adsorption of arsenic by one-step fabrication of alum sludge and graphitic carbon nitride (g-C3N4)

Jong Gook Kim, Hye Bin Kim, Geun Seok Yoon, Seon Hee Kim, Su Jin Min, Daniel C.W. Tsang, Kitae Baek

Research output: Journal article publicationJournal articleAcademic researchpeer-review

12 Citations (Scopus)

Abstract

The oxidation of trivalent arsenic (As(III)) to pentavalent arsenic (As(V)) is a common pretreatment to remove As(III) from the aqueous phase. The graphitic carbon nitride as a photocatalyst can transform As(III) to As(V), but the photocatalyst does not adsorb any species of arsenic. In this study, a new composite material to achieve the simultaneous oxidation and adsorption of arsenic was synthesized by co-pyrolyzing alum sludge and melamine. It was hypothesized that graphitic carbon nitride derived from melamine oxidizes As(III) to As(V) and pyrolyzed alum sludge provides strong adsorption sites for the oxidized As(V). The composites were characterized by X-ray diffraction, Brunauer-Emmett-Teller(BET) surface, scanning electron microscope, and X-ray photoelectron spectrometer. The composite material effectively converted As(III) to As(V) under the light, and the total arsenic concentration decreased in the aqueous phase via the adsorption of As(V). Speciation analysis of arsenic on the composite showed that both As(III) and As(V) species were present on the surface of adsorbent, from which desorption by mixing with deionized water was difficult. This new and green composite material can oxidize As(III) and adsorb arsenic simultaneously under the light, which can be used to treat arsenic-containing water.

Original languageEnglish
Article number121138
JournalJournal of Hazardous Materials
Volume383
DOIs
Publication statusPublished - 5 Feb 2020

Keywords

  • Arsenic speciation
  • Drinking water treatment
  • Green photocatalyst
  • Sustainable remediation
  • Waste valorization/recycling

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution
  • Health, Toxicology and Mutagenesis

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