Degradation of polychlorinated dibenzo-p-dioxins and dibenzofurans in real-field soil by an integrated visible-light photocatalysis and solvent migration system with p-n heterojunction BiVO4/Bi2O3

Yonghyeon Lee; Mingcan Cui; Jongbok Choi; Jeonggwan Kim; Younggyu Son; Jeehyeong Khim

doi:10.1016/j.jhazmat.2017.12.002

Degradation of polychlorinated dibenzo-p-dioxins and dibenzofurans in real-field soil by an integrated visible-light photocatalysis and solvent migration system with p-n heterojunction BiVO₄/Bi₂O₃

J Hazard Mater. 2018 Feb 15:344:1116-1125. doi: 10.1016/j.jhazmat.2017.12.002. Epub 2017 Dec 6.

Authors

Yonghyeon Lee¹, Mingcan Cui¹, Jongbok Choi¹, Jeonggwan Kim², Younggyu Son³, Jeehyeong Khim⁴

Affiliations

¹ School of Civil, Environmental and Architectural Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea.
² Korea Environmental Industry & Technology Institute, 215, Jinheung-ro, Eunpyeong-gu, Seoul 03367, Republic of Korea.
³ Department of Environmental Engineering, Kumoh National Institute of Technology, 61, Daehak-ro, Gumi, Gyeongsangbuk-do 39177, Republic of Korea.
⁴ School of Civil, Environmental and Architectural Engineering, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 02841, Republic of Korea. Electronic address: hyeong@korea.ac.kr.

PMID: 30216971
DOI: 10.1016/j.jhazmat.2017.12.002

Abstract

Degradation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in real-field soil was conducted using an integrated photocatalysis-solvent migration system of BiVO₄/Bi₂O₃ and n-hexane. The photocatalyst BiVO₄/Bi₂O₃ was synthesized, and its performance was found to be affected by the BiVO₄ content, with 20wt% BiVO₄ showing the best performance owing to its p-n heterojunction being well formed. Migration was affected by the amount of n-hexane, with 15% n-hexane giving the most effective transportation of PCDD/Fs. 37.2% of 17 PCDD/Fs was removed in 60h by the integrated photocatalysis-solvent migration system, although the reaction zone covered 8.5% of the volume of the soil. The result showed that migration via n-hexane fulfilled the aim of carrying contaminants from inside of the soil to the surface. Electron-scavenging experiments with BiVO₄/Bi₂O₃ showed an 18.4% of performance in removal compared to no-scavenging condition, which showed that the main reactions driving BiVO₄/Bi₂O₃ visible-light photocatalysis for aryl-chloride were found to be reduction-based. Owing to the hindering effect of Cl atoms, degradation by hydroxyl radical could proceed after initial dechlorination. This study establishes the applicability of integrated photocatalysis-solvent migration systems in real-field settings, and is the first report of a visible-light photocatalyst, BiVO₄/Bi₂O₃, for the degradation of PCDD/Fs in soil.

Keywords: PCDD/F; Real-field soil; Solvent; Visible-light photocatalysis; p-n Heterojunction photocatalyst.

Publication types

Research Support, Non-U.S. Gov't