Composition-structure-function correlation of Ca/Zn/AlOx catalysts for the ketonization of acetic acid

Catalytic ketonization of palmitic acid over a series of transition metal oxides supported on zirconia oxide-based catalysts

“…66 Based on all these result, a balance of Lewis acid-base M x+ -O 2À pairs seem to be a dening characteristic of good ketonization catalyst. [67][68][69][70] Apart from this, the impact of catalyst textural properties in palmitic acid ketonization reaction remains unclear. Even though a slight improvement in surface area and porosity occurred with dopant addition, it is not translated into higher catalytic activity or ketone yield.…”

Catalytic Pyrolysis of Aliphatic Carboxylic Acids into Symmetric Ketones over Ceria-Based Catalysts: Kinetics, Isotope Effect and Mechanism

“…Conversion and selectivity are highly dependent on reaction conditions, especially temperature. The effect of the reaction temperature on the degree of conversion and selectivity to ketone was studied [16,37,64]. It was shown that an increase in temperature to 425 • C allows the conversion of acetic acid to be achieved at about 93%-100% [16,64].…”

“…The effect of the reaction temperature on the degree of conversion and selectivity to ketone was studied [16,37,64]. It was shown that an increase in temperature to 425 • C allows the conversion of acetic acid to be achieved at about 93%-100% [16,64]. Importantly, the highest conversion of propionic acid on the zirconium surface was observed at a temperature of the highest ketonization rate [37].…”

“…The ketonization reaction, or ketonic decarboxylation is one of the attractive ways to convert carboxylic acids into sustainable biofuels and valuable industrial products with high added value [15][16][17][18][19][20][21][22][23]. Ketonization provides for the formation of a new C-C bond in one step, preserves the initial functional group C = O, and significantly reduces the oxygen content in the molecule [15][16][17][18][19][20][21][22][23]. Ketonization provides for the formation of a new C-C C-C bond in one step, preserves the initial functional group C = O, and significantly reduces the oxygen content in the molecule due to decarboxylation and dehydration.…”

“…Despite the close attention to the ketonization reaction, last year's publications [15][16][17][18], including numerous studies and reviews [16,17,[19][20][21][22][23] suggested that the mechanism of this reaction is not completely clear. Over the past few decades, several basic mechanisms of this reaction have been proposed : (i) free-radical mechanism [24], (ii) direct concerted mechanism [20,25], (iii) mechanism involving an acyl intermediate [26], (iv) ketene based mechanisms [27][28][29], (v) and a betaketo-acid-intermediate based mechanisms [30][31][32][33][34][35] (Scheme 1).…”