Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
235728 | Powder Technology | 2015 | 8 Pages |
•CuO-NPs allow N2O reduction using SiO2 as support with different porosity orders.•Mesoporous ordered SiO2 framework is crucial for N2O reduction enhancement.•N2O reduction at low temperature is possible in CO presence.•N2O total reduction at 400 °C over CuO-NPs/SiO2 spherical catalysts
A N2O reduction study in the presence of CO, used as a scavenging agent, was carried out in order to understand the role played by the SiO2 morphology and mesoporosity order. Physicochemical properties were characterized by means of low angle X-ray diffraction, N2 physisorption, FESEM, HRTEM and HAADF microscopies. Highly ordered mesoporous SiO2 was obtained by the Stöber modified method. On the other hand, disordered-pore-amorphous SiO2 with broad pore-size distribution was synthesized by the sol–gel method. The CuO functionalization of SiO2 materials was carried out by incipient impregnation using citric acid. The role played by the Cu wt.% during the reduction of the greenhouse gas was examined in the N2O reduction. The ordered mesoporosity with a sharp pore size distribution results to be crucial for enhancing the N2O reduction from 200 °C; the copper functionalized xerogel and commercial materials started the N2O conversion at 350 °C. Low-temperature reduction was exhibited when the CuO functionalization percentage was 10 wt.%, and total conversion was achieved from 200 to 400 °C, also showing good stability for 21 h. CuO—supported on highly ordered mesoporous SiO2 is comparable with other Rh and Pd systems reported in the literature.
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