Porous stainless-steel fibers supported CuCeFeOx/Zeolite catalysts for the enhanced CO oxidation: Experimental and kinetic studies

Abstract

To develop novel catalysts of high-performance and cost-effectiveness, and to investigate the reaction kinetics of CO oxidation, ternary CuCeFeOx catalysts supported on zeolite/PSF (porous stainless-steel fibers) were synthesized for the first time. Effects of different Ce/Fe ratios, loading amounts, calcination temperatures, and reaction kinetics were investigated. Remarkably improved catalytic performance was achieved in the PSF-supported catalysts compared to the granular ones, owing to the increased mass/heat transfer efficiency and the high dispersion of active metal oxide species anchored on the zeolite layer. The Cu3Ce12Fe4-400 sample exhibited the best catalytic activity with a temperature difference in T90 of almost 40 °C lower than the worst one. Characterization results from XRD, FTIR, TEM, XPS, H2-TPR, etc. revealed that the promoted reducibility of metal oxides and formation of more oxygen vacancies significantly contributed to the enhanced catalytic activity. Furthermore, a generalized rate expression was derived from intrinsic and macro kinetic studies by assuming the conversion of CO to CO2 as the rate-determining step, in which CO oxidation over the PSF-supported catalysts followed the pseudo-first-order kinetic established by the Langmuir-Hinshelwood type mechanism.