Selective Oxidation of D‐Galactose over Gold Catalysts

Abstract

Scheme 1. Selective oxidation of d-galactose to galactonolactone and further to galactonic acid by molecular oxygen over the gold catalyst.[a] B.

Catalysis for Lignocellulosic Biomass Processing: Methodological Aspects

“…An increase of the particle size was observed with an increase in the concentration of the initial HAuCl 4 solution as well as calcination temperature [66,67]. It was demonstrated that arabinose as well as galactose oxidations are structure sensitive.…”

“…9 demonstrated [65] that the position of the maximum in turnover frequency depends on the cluster size and that reaction parameters (partial pressures of reactants) can influence this position. An example of cluster size dependence of the activity on the cluster size related to catalytic transformations of biomass derived chemicals, is oxidation of sugars over gold catalysts [66,67], in particular selective oxidation of arabinose to arabinonic acid (Fig. 8).…”

“…This relationship was explained by the cluster size depending availability of low-coordinated atoms, which are the active sites for the oxygen activation, the arabinose adsorption and the dehydrogenation of the anomeric carbon. A kinetic model, explicitly considering the cluster size, was based on a theoretical approach [65] and was utilized in [66,67] to obtain a quantitative description of the cluster size dependence data (Fig. 9).…”

Catalysis for Lignocellulosic Biomass Processing: Methodological Aspects

“…9 demonstrated [66] that the position of the maximum in turnover frequency depends on the cluster size and that reaction parameters (partial pressures of reactants) can influence this position. An example of cluster size dependence of the activity on the cluster size related to catalytic transformations of biomass derived chemicals, is oxidation of sugars over gold catalysts [67,68], in particular selective oxidation of arabinose to arabinonic acid (Fig. 8).…”

“…Au/Al 2 O 3 catalysts with varying metal dispersion were synthesized using different preparation methods and conditions [67]. An increase of the particle size was observed with an increase in the concentration of the initial HAuCl 4 solution as well as calcination temperature [67,68]. It was demonstrated that arabinose as well as galactose oxidations are structure sensitive.…”