Reaction Steps in Heterogeneous Photocatalytic Oxidation of Toluene in Gas Phase-A Review.
Fiche publication
Date publication
septembre 2023
Journal
Molecules (Basel, Switzerland)
Auteurs
Membres identifiés du Cancéropôle Est :
Pr SCHNEIDER Raphaël
Tous les auteurs :
Tulebekov Y, Orazov Z, Satybaldiyev B, Snow DD, Schneider R, Uralbekov B
Lien Pubmed
Résumé
A review of the current literature shows there is no clear consensus regarding the reaction mechanisms of air-borne aromatic compounds such as toluene by photocatalytic oxidation. Potential oxidation reactions over TiO or TiO-based catalysts under ultraviolet and visible (UV/VIS) illumination are most commonly considered for removal of these pollutants. Along the pathways from a model pollutant, toluene, to final mineralization products (CO and HO), the formation of several intermediates via specific reactions include parallel oxidation reactions and formation of less-reactive intermediates on the TiO surface. The latter may occupy active adsorption sites and causes drastic catalyst deactivation in some cases. Major hazardous gas-phase intermediates are benzene and formaldehyde, classified by the International Agency for Research on Cancer (IARC) as Group 1 carcinogenic compounds. Adsorbed intermediates leading to catalyst deactivation are benzaldehyde, benzoic acid, and cresols. The three most typical pathways of toluene photocatalytic oxidation are reviewed: methyl group oxidation, aromatic ring oxidation, and aromatic ring opening.
Mots clés
photocatalytic oxidation, reaction pathways, titanium dioxide, toluene
Référence
Molecules. 2023 09 6;28(18):