Effect of Pt promotion on Ni/Al[sub 2]O[sub 3] for the selective catalytic reduction of NO with hydrogen

Abstract

Ni/Al2O3 (10 wt.% Ni) and Ni-Pt/Al2O3 (10 wt.% Ni, 0.5 wt.% Pt) were comparatively tested in the hydrogen selective catalytic reduction process (H2-SCR), at reaction temperatures below 350°C. Catalytic activity tests consisted in temperature programmed reactions (TPRea) under plug flow conditions from 50 to 350°C, with a temperature rate of 5°C/min, using a feed stream with a reactant ratio NO:H2 = 1:1.3 and a GHSV of 4500 h−1. Promotion with Pt increases the catalytic performances of the Ni based catalyst, in respect to NO conversion, N2 selectivity and N2 yield. The reaction temperatures for NO conversion above 95% decrease significantly due to Pt addition, from 250°C for Ni/Al2O3 to 125°C for Ni-Pt/Al2O3. Characterization of catalysts was performed by: X ray powder diffraction (XRD) for the estimation of Ni crystallite size, temperature programmed reduction (TPR) for the catalyst reducibility, temperature programmed desorption of hydrogen (H2-TPD) for the investigation of active sites and metal dispersion on the support, N2 adsorption-desorption isotherms at −196°C for the determination of total specific surface area and pore size distribution, and H/D isotopic exchange on the catalyst surface.At the request of the Proceedings Editor, and all authors of the paper, an updated version of this article was published on 14 January 2014. Data presented in Table 1 of the original paper contained errors which have been corrected in the updated and re-published article. The Corrigendum attached to the corrected article PDF file explains the errors in more detail.