On the hydrogen absorption and release capabilities of precious metals
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This post was last edited by jordan569 on 2013-1-6 at 21:43. Precious metals are added to F-T catalysts as additives; thanks to their unique ability to absorb and release hydrogen, they generate active hydrogen, which is then transferred to the unreduced Co oxides in the catalyst through the hydrogen overflow effect, thereby improving the catalyst’s reduction capacity. In fact, different precious metals have varying capacities for hydrogen absorption and release. So, what is the approximate order of hydrogen absorption and release capacity for common precious metal additives such as Re, Pt, Pd, Ru, and Rh? Are there any specific data related to hydrogen absorption and release? . Note $ # , $ $
The role of these precious metal promoters is not merely to promote catalyst reduction through hydrogen spillover. You can look up some articles on the hydrogen chemical adsorption of these precious metals; there will be comparisons of the strength of adsorption. Or one can prepare these precious metal catalysts by themselves for H2-TPD, and results can also be obtained; it’s not very difficult. Or the most straightforward approach is to use catalysts with the same content of additives, and by performing a TPR analysis, it is possible to roughly compare the differences in the reducibility of these catalysts. Perhaps you have already done this; you’re just looking for such hydrogen adsorption data to support the results regarding reducibility?
The approximate order might be Pt > Pd > Rh > Ru > Re. I have carried out TPR and TPD analyses, but I would like to support my conclusions with data from other sources, such as quantitative figures regarding the hydrogen absorption and release capabilities of these precious metals.
This post was last edited by fossil-zhang on 2010-3-23 at 18:35. It depends on what kind of data you want; the most straightforward approach is to look up the adsorption heat of hydrogen on these metal atoms. You can find relevant information in various books and early scientific publications. I remember that Wu Yue’s book \"Catalytic Chemistry\" discusses the properties of different metal-hydrogen bonds, and it may provide some data.