Chlorobenzene degeradation by non-thermal plasma combined with EG-TiO2/ZnO as a photocatalyst: Effect of photocatalyst on CO2 selectivity and byproducts reduction

Farshid Ghorbani Shahna; Abdulrahman Bahrami; Iraj Alimohammadi; Rassuol Yarahmadi; Babak Jaleh; Mastaneh Gandomi; Hossein Ebrahimi; Kamal Ad-Din Abedi

doi:10.1016/j.jhazmat.2016.11.025

Chlorobenzene degeradation by non-thermal plasma combined with EG-TiO₂/ZnO as a photocatalyst: Effect of photocatalyst on CO₂ selectivity and byproducts reduction

J Hazard Mater. 2017 Feb 15;324(Pt B):544-553. doi: 10.1016/j.jhazmat.2016.11.025. Epub 2016 Nov 9.

Authors

Farshid Ghorbani Shahna¹, Abdulrahman Bahrami¹, Iraj Alimohammadi², Rassuol Yarahmadi², Babak Jaleh³, Mastaneh Gandomi³, Hossein Ebrahimi⁴, Kamal Ad-Din Abedi⁵

Affiliations

¹ Center of Excellence for Occupational Health and Research Center for Health Science, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
² Department of Occupational Health, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
³ Faculty of Science, Physics Department, Bu-Ali Sina University, Hamedan, Iran.
⁴ Department of Occupational Health, School of Public Health, Iran University of Medical Sciences, Tehran, Iran. Electronic address: hossein.ebrahimi@yahoo.com.
⁵ Department of Occupational Health Engineering, Faculty of Health, Kurdistan University of Medical sciences, Sanandaj, Iran.

PMID: 27887812
DOI: 10.1016/j.jhazmat.2016.11.025

Abstract

The non-thermal plasma (NTP) technique, which suffers from low selectivity in complete oxidation of volatile organic compounds to CO₂ and H₂O, creates unwanted and harmful byproducts. NTP in concert with photocatalyst can resolve this limitation due to additional oxidation. TiO₂ and ZnO nanoparticles were coated on the surface of the expanded graphite and placed downstream of the NTP reactor under UV light. In this study, to compare the performance of NTP and the combined system, chlorobenzene removal, selectivity of CO₂ and byproducts formation were investigated. The results showed that the combined system enhanced both the removal efficiency and CO₂ selectivity. The output gas of the NTP reactor contained chlorobenzene, phosgene, O₃, NO, NO₂, CO, CO₂, HCL and CL. The bulk of these byproducts was oxidized on the surface of the nanocomposite; as a result, the content of the byproducts in the output gas of the combined system decreased dramatically. The removal efficiency and CO₂ selectivity increased by rising the applied voltage and residence time because the collision between active species and pollutant molecules increases. Based on these results, the combined system is preferred due to a higher performance and lower formation of harmful byproducts.

Keywords: Byproducts reduction; Expanded graphite; Non-thermal plasma; Photocatalyst; TiO(2)/ZnO catalysts.