(6az) The Synergistic Effect of Copper and Niobium Species on a Novel Cu/Nb-Ti Mixed Oxide Catalyst for the Selective Catalytic Reduction of NOx with NH3
- Conference: AIChE Annual Meeting
- Year: 2018
- Proceeding: 2018 AIChE Annual Meeting
- Group: Meet the Faculty Candidate Poster Session – Sponsored by the Education Division
- Time: Sunday, October 28, 2018 - 1:00pm-3:30pm
Teaching Interests: An array of analytical techniques (HRTEM, XRD, LRS, XPS, EPR, in-situ DRIFTS etc.) were employed to elucidate the correlations among the âperformance â structure â propertyâ and the reaction mechanism over 0.8%Cu/Ti2NbOx catalyst. The introduction of niobium oxide increased the surface area of TiO2 and decreased the crystallite size, promoting the high dispersion of copper species. Meanwhile, the total acidity and the amount of surface active oxygen over the catalyst were increased by the addition of niobium oxide. Copper species mainly existing in the state of isolated Cu2+ and non-isolated Cu+ enhanced the redox capability of the catalyst and the highest ratio of isolated Cu2+/copper species resulted in an excellent catalytic performance of 0.8%Cu/Ti2NbOx. The promotional synergistic effect of copper and niobium in 0.8%Cu/Ti2NbOx catalyst gave rise to a better NH3-SCR performance. Furthermore, the reaction pathway over 0.8%Cu/Ti2NbOx catalyst followed both Eley-Rideal mechanism and Langmuir-Hinshelwood mechanism at 225oC. Both coordinated NH3 and ionic NH4+ were active intermediates and monodentate nitrates, bidentate nitrates and bridging nitrates were involved in the reaction over 0.8%Cu/Ti2NbOx catalyst at the reaction temperature of 225oC.