Preferential CO oxidation in a hydrogen-rich stream over gold supported on Ni–Fe mixed metal oxides for fuel cell applications. (30th January 2016)

• Record Type: Journal Article
• Authors: Qwabe, Lindelani Q.; Dasireddy, Venkata D.B.C.; Singh, Sooboo; Friedrich, Holger B.
• Is Part Of: International journal of hydrogen energy. Volume 41:Number 4(2016)
• Page Start: 2144
• Page End: 2153
• Publication Date: 2016-01-30
• Subjects: Preferential oxidation -- Gold -- Mixed metal oxide -- Hydrogen -- Carbon monoxide; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2015.12.060
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: This paper reports the catalytic performance of gold nanoparticles supported on high surface area mixed metal oxides derived from Ni and Fe hydrotalcite-like precursors. The gold catalysts were prepared by deposition-precipitation and characterised by XRD, TGA, BET, H2 -TPR, XPS, ICP and HR-TEM. From HR-TEM analysis, gold particles ranging from 4 to 10 nm were observed. XPS surface analysis revealed that gold existed in the metallic state, whereas surface oxides were NiO and Fe2 O3 . For the preferential CO oxidation reaction, the 1.5 wt.% Au catalyst gave almost complete conversion (≈40% selectivity) at 60 °C using 2 vol.% O2 with the GHSV fixed at 12 000 h −1 . The addition of CO2 to the feed stream resulted in a 10–15% decrease in conversion, whereas the addition of H2 O improved CO conversion. The addition of H2 O to the feed containing CO2 showed signs that H2 O mitigated the negative effect of CO2 . Graphical abstract: Highlights: Preparation of Ni–Fe mixed metal oxides from Ni–Fe hydrotalcite-like precursors. Gold particles ranging from 4 to 10 nm deposited on Ni–Fe oxide supports. Almost complete conversion of CO was possible at low temperatures. In the PROX reaction, H2 O mitigated the negative effect of CO2 .