Ketonization of acetic acid on titania-functionalized silica monoliths

Reforming reactions of acetic acid on nickel catalysts over a wide temperature range

“…This is not surprising, since this reaction is thermodynamically favoured in this temperature range [27]. The ketonization reaction is known to take place on polycrystalline oxide samples, and numerous oxides have been found to promote it [28]. However, the ketonization reaction seems to depend strongly on acidity/ basicity characteristics of the catalyst.…”

Ketonization of carboxylic acids over CeO2-based composite oxides

“…A number of articles on the ketonization of carboxylic acids are available: several oxides, such as Cr 2 O 3 [9,10], Al 2 O 3 [11,12], PbO 2 [12], TiO 2 [13][14][15][16], ZrO 2 [14,[17][18][19], CeO 2 [19][20][21][22][23][24], iron oxide [14,15,[25][26][27], and manganese oxide [12,19,20,22,28], as well as Mg/Al hydrotalcites [29] catalyze the ketonization of carboxylic acids. Many other catalysts have been found since the 19th century: BaCO 3 , MgO, ThO 2 , UO 2 , CdO, ZnO, NiO, Bi 2 O 3 , and SnO 2 have been introduced in references [12,30].…”

Base-Catalyzed Reactions in Biomass Conversion: Reaction Mechanisms and Catalyst Deactivation

“…FTIR and XRD studies corroborate that the most stable adsorption of acetic acid on the catalytic surface is by bridging bidentate configurations, concluding that a surface containing doubly unsaturated cations must be presented [140]. Amphoteric reducible metal oxides, such as CeO 2 , TiO 2 , and ZrO 2 , have been reported to be the most active catalysts for ketonization, observing a high impact of the preparation and activation method [141][142][143]. Materials calcined at higher temperature gave significantly greater rates of ketonization, as did preparation methods that increase the surface area.…”

“…This mechanism is still not defined, but the existence of this intermediate was observed by FTIR combined with isotopic labeling studies [154]. Presently, it is considered more as a side reaction than an alternative mechanism to the main ketonization, in such a way that ethenone was identified during studies of acetic acid ketonization [142].…”