Adsorption/catalytic combustion of toxic 1,2-dichloroethane on multifunctional Nb2O5-TiO2 composite metal oxides

Abstract The Nb 2 O 5 -TiO 2 catalyst system was synthesized via sol-gel method and investigated for adsorption/catalytic combustion of toxic 1,2-dichloroethane (DCE), which was usually recognized as a representative of various chlorinated and brominated VOCs pollutants. The research results of structure-performance relationship revealed that binary Nb 2 O 5 -TiO 2 were amorphous and mesoporous materials with pore diameter mainly in the range of 2–10 nm, and Nb and Ti elements were uniformly dispersed. The interaction between Nb 2 O 5 and TiO 2 coupled with the molar ratio of Nb/Ti improved the physicochemical properties of Nb 2 O 5 -TiO 2 . Moreover, Nb 2 O 5 -TiO 2 exhibited higher catalytic activity for DCE combustion than single Nb 2 O 5 or TiO 2 . Especially, the 2Nb1Ti catalyst (Nb/Ti = 2:1, molar ratio) displayed the highest activity, over which 90% conversion of DCE could be achieved at 295 °C. These results were related to that the interaction effect between Nb 2 O 5 and TiO 2 improved acidity and oxidizing properties, and the materials had large surface area, all of which were favorable for adsorbing DCE at relatively low temperatures (below 93 °C) on Nb 2 O 5 -TiO 2 and then improving catalytic combustion performance at lower reaction temperatures than Nb 2 O 5 or TiO 2 . Besides, during the long-term continuous reaction, even though partial deactivation was observed for this catalyst, it could be suppressed at elevated temperature.