Abstract
A series of potassium promoted Ru/meso-macroporous SiO2 catalysts were prepared and used for the preferential oxidation of CO (CO-PROX) in H2-rich gases. The catalysts were characterized by using techniques of TEM, SEM TPR, XPS, and N2 adsorption/desorption. The catalytic activity of Ru/meso-macroporous SiO2 was markedly improved by the introduction of potassium. The catalyst of K-5 wt.% Ru/meso-macroporous SiO2 with molar ratio of K:Ru = 5:7 exhibited relatively high activity and selectivity for CO-PROX. Nanoparticles of ruthenium species can be highly dispersed on the meso-macroporous SiO2 support by the simple impregnation method. The addition of potassium weakened the interaction between metallic Ru and the silica support. Lowering the reduction temperature of ruthenium ions could keep ruthenium in the state of metallic Ru, and it was proposed that potassium acted as an electron donating agent. The electron donating effect of potassium improved the low temperature activity for CO oxidation and increased the selectivity of O2 for CO oxidation, thus K-modified Ru/meso-macroporous SiO2 catalyst showed obviously a wide temperature window for CO elimination from H2-rich gases, meanwhile the related mechanism was discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
