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Insights into support effects of Ag/SiO2 catalysts for dimethyl glycolate semi-hydrogenation to methyl glycolate.
- Source :
-
Molecular Catalysis . Apr2024, Vol. 559, pN.PAG-N.PAG. 1p. - Publication Year :
- 2024
-
Abstract
- • Ordered mesoporous supports endow good dispersion of Ag nanoparticles. • Ag/SiO 2 catalysts show remarkable support effects on both activity and selectivity. • Supports effects originate from distinct activation and diffusion behaviors. • Competitive-adsorption of H 2 versus DMO dominates DMO semi-hydrogenation. Support materials play vital roles in heterogenous catalysis via the so-called support effects, and understanding on the support effects is beneficial for the design of high-performance catalysts. Herein, we represent detailed investigations on the support effects of Ag catalysts for dimethyl glycolate (DMO) semi-hydrogenation to methyl glycolate (MG), where G6 silica with amorphous mesopores, SBA-15 with parallel mesopores and silica nanospheres (MSNS) with center-radial ones were employed as the supports. The hydrogenation activity decreases in the order of Ag/MSNS > Ag/SBA-15 > Ag/G6 while the MG selectivity in the order of Ag/G6 > Ag/MSNS > Ag/SBA-15 at the same reaction conditions, indicating remarkable support effects on both activity and selectivity. Structural characterizations, temperature programmed experiments and in-situ FTIR of DMO adsorption experiments demonstrate that the weak confinement effect of G6 leads to the larger sized Ag nanoparticles and weakened activation of DMO and H 2 , which contributes to low hydrogenation activity. In contrast, the ordered mesoporous SBA-15 and MSNS deliver well confinement effects for Ag nanoparticles and the activation of DMO and H 2 , but the distinct pore structures result in different activation and diffusion behaviors. Finally, DMO conversion and MG yield are well correlated with the competitive adsorption of H 2 versus DMO on Ag catalysts, indicating such competitivity as a descriptor for DMO semi-hydrogenation over Ag catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]
- Subjects :
- *SILICON oxide
*CATALYSTS
*ETHANES
*HYDROGENATION
*NANOPARTICLES
Subjects
Details
- Language :
- English
- ISSN :
- 24688231
- Volume :
- 559
- Database :
- Academic Search Index
- Journal :
- Molecular Catalysis
- Publication Type :
- Academic Journal
- Accession number :
- 176542945
- Full Text :
- https://doi.org/10.1016/j.mcat.2024.114109