Hydrogenation of CO2 Over Copper, Silver and Gold/Zirconia Catalysts: Comparative Study of Catalyst Properties and Reaction Pathways

Low temperature water gas shift over gold catalysts

“…The data obtained showed the relation between the nature of the support, its state and structure and their influence on gold dispersion, which reflect on the WGS activity of gold catalysts. One possible explanation for the observed differences in the catalytic behaviour of the catalysts studied by Baiker (37) and those prepared in our laboratory could be related to the difference in size of the metal particles -3.4 nm in the former case and below 3 nm in the latter. As stated above, a 2.5 -3 nm particle size is crucial for WGS activity.…”

“…The effect of the support's precursor was studied by Kozlova et al (36) who have found that the use of amorphous as-precipitated iron-hydroxide Fe(OH)3* permits the preparation of highly active gold catalysts for LT CO oxidation. Baiker et al (37,38) showed that the degree of crystallization of zirconia supports for gold, silver and copper catalysts strongly affects their activity for methanol synthesis and reverse WGS. They found that the crystallization of amorphous zirconia results in significantly lower activity and selectivity in the above reactions (37).…”

“…Baiker et al (37,38) showed that the degree of crystallization of zirconia supports for gold, silver and copper catalysts strongly affects their activity for methanol synthesis and reverse WGS. They found that the crystallization of amorphous zirconia results in significantly lower activity and selectivity in the above reactions (37). Taking into account the above-mentioned considerations, we prepared gold catalysts on amorphous or not well-crystallized zirconia, zinc oxide and the mixed oxide systems Fe2O3-ZnO and Fe2O3-ZrO2.…”

Utilization of carbon dioxide in heterogeneous catalytic synthesis

“…Another common feature is that the support plays a significant role in the overall catalytic performance. [25][26][27][28] Zirconia proved to be an excellent support material for CO 2 -based methanol synthesis. The preparation, structural and chemical properties, as well as the mechanistic aspects of metal-zirconia catalysts, for CO 2 hydrogenation have been reviewed recently.…”

Doped-ZrO2 aerogels: Catalysts of controlled structure and properties

“…With the development and application of sol-gel chemistry and supercritical drying, aerogels can be produced with high surface area [7,8] and then can be wash-coated onto supports [2]. The oxide/metal doped-ZrO2 aerogels not only showed very high thermal stability but also had promising catalytic performance in hydrogenation [1] and oxidation [2,[9][10][11][12] reactions. Use of sol-gel chemistry for these promising materials is considered here and especially aerogels; this is potentially interesting in the production of materials of controlled texture and high reactivity.…”