Abstract
Ruthenium catalysts supported on SiO 2, Al 2O 3 and TiO 2 were prepared by the impregnation method. Temperature-programmed desorption (TPD) method was applied to investigate the kinetics of hydrogen adsorption/desorption on these catalysts. All the TPD results show two-peak profile, except Ru/SiO 2. The low-temperature peak was assigned to the hydrogen adsorbed on the Ru metal. The high-temperature peak was attributed to the spillover of hydrogen atoms from metal to the support. Both are activated process. The amount of adsorbed hydrogen increased with increasing adsorption temperature, and the maximum adsorption occurs at above 200 °C. The activation energy of adsorption is a function of catalyst support and the reduction temperature. It decreases in the order of Ru/TiO 2 (500 °C reduction)>Ru/Al 2O 3>Ru/TiO 2 (300 °C reduction)>Ru/SiO 2. The results demonstrated that the strong metal–support interaction exerted on Ru/TiO 2 would suppress hydrogen chemisorption at room temperature due to its high activation energy. However, hydrogen chemisorption on Ru/TiO 2 was not suppressed at high temperature. One is able to measure the Ru dispersion by adsorption of hydrogen at high temperature.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.