Influence of Functionalized Carbon Nanotubes on Catalytic Activity of V 2 O 5 /TiO 2 ‐CNTs for 1, 2‐Dichlorobenzene Oxidation

Carbon nanotubes (CNTs) with or without oxygen-containing functional groups (e.g., hydroxy radical [OH] and carboxyl [COOH] group) were used in combination with titanium dioxide (TiO2) to support vanadium oxide as novel catalysts (i.e., V2O5/TiO2-CNTs-OH [V/Ti-CNTs-OH], V2O5/TiO2-CNTs-COOH [V/Ti-CNTs-COOH], and V2O5/TiO2-CNTs [V/Ti-CNTs]). These catalysts were used to catalytically decompose gaseous 1,2-dichlorobenzene (1,2-DCBz) at low temperature (150 degrees C). The results of this study indicate that the catalytic activity of V/Ti-CNTs evidently improved by the introduction of oxygen-containing functional groups, and particularly the V/Ti-CNTs-COOH catalyst showed excellent catalytic performance at low temperature. Oxygen-containing functional groups in CNTs increase the active chemisorbed oxygen amount, thus improve both the oxygen delivery capability and the surface lattice oxygen mobility of the catalysts. The former guarantees an efficient 1,2-DCBz oxidation and retards the catalyst deactivation in oxygen-free atmosphere. The latter ensures the regeneration of the deactivated catalyst when oxygen is reinjected into reaction atmosphere. Or else, the surface oxygen vacancy caused by the consumption of surface reactive oxygen would be difficult to be replenished by the oxygen from atmosphere at low temperature (150 degrees C). These results reveal the effect of oxygen-containing functional groups on the structure-catalytic property of V/Ti-CNTs catalyst, suggesting that controlling the emission of chloro-aromatic pollutants from incineration flue gas could be achieved by modifying the surface of the catalyst containing CNTs with proper oxygen-containing functional groups. (c) 2019 American Institute of Chemical Engineers Environ Prog, 38: e13221, 2019