Influence of the ionic liquid presence on the selective oxidation of glucose over molybdenum based catalysts

Influence of gold particle size in Au/C catalysts for base-free oxidation of glucose

“…Industrially D-Gluconic acid is produced by enzymatic fermentation process [13,14] for which the principal inconvenient for sustainable largescale production is the necessity of a neutralization step in order to avoid enzymes deactivation by the produced acid [15]. This problem could be solved either by using a base or by the substitution of the enzymes with a heterogeneous catalyst able to oxidize glucose under mild base-free conditions by using either O2 or H2O2 as oxidants [16][17][18][19].…”

“…Industrially D-Gluconic acid is produced by enzymatic fermentation process [13,14] for which the principal inconvenient for sustainable largescale production is the necessity of a neutralization step in order to avoid enzymes deactivation by the produced acid [15]. This problem could be solved either by using a base or by the substitution of the enzymes with a heterogeneous catalyst able to oxidize glucose under mild base-free conditions by using either O2 or H2O2 as oxidants [16][17][18][19].Although the use of base (NaOH and a relatively high pH of around 9-9.5) results in increase of heterogeneous catalyst's activity due to particle size stabilization and metal leaching suppression [20][21][22], a decrease in the selectivity to gluconic acid is often observed caused by the glucose to fructose isomerization process [23]. In addition, the formation of gluconate salt instead of pure gluconic acid occurs and entails the need of cost effective post-reaction treatment to obtain the target acid.…”

Production of Hexaric Acids from Biomass

“…Production of hexaric acids catalyzed by metals has been of industrial interest since the 1940s [77,78,79,80,81]. Following these antecedent works, several studies have been reported [68,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98]. Although Pt [76,82,83,84,91,92,97] and Au [68,84,85,86,89,94,95,96] have been used as catalysts frequently, other elements like Ti [87,88], Mn [90], Fe [98], Mo [93], and Pd [91,99] can also be incorporated in catalyst composites.…”

“…Following these antecedent works, several studies have been reported [68,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98]. Although Pt [76,82,83,84,91,92,97] and Au [68,84,85,86,89,94,95,96] have been used as catalysts frequently, other elements like Ti [87,88], Mn [90], Fe [98], Mo [93], and Pd [91,99] can also be incorporated in catalyst composites. Aldohexoses [84,85,86,87,88,90,91,92,93,94,95,97,98], aldohexonic acids [82,83,84], and hexuronic acid [68,89,96], in addition to the corresponding sugar alcohol [76,85], can be starting compounds for the metal-catalyzed production of hexaric acids.…”

“…Although Pt [76,82,83,84,91,92,97] and Au [68,84,85,86,89,94,95,96] have been used as catalysts frequently, other elements like Ti [87,88], Mn [90], Fe [98], Mo [93], and Pd [91,99] can also be incorporated in catalyst composites. Aldohexoses [84,85,86,87,88,90,91,92,93,94,95,97,98], aldohexonic acids [82,83,84], and hexuronic acid [68,89,96], in addition to the corresponding sugar alcohol [76,85], can be starting compounds for the metal-catalyzed production of hexaric acids. In addition to the use of oxidants like H 2 O 2 and O 2 , electrochemical [85,90] and photochemical [87,88] oxidation of the substrates has been examined.…”