Selective liquid phase oxidation of glycerol to glyceric acid over novel supported Pt catalysts

Abstract

Several supported platinum catalysts were prepared by extractive-pyrolytic method for the selective glyceric acid production from glycerol. Al2O3, Y2O3, Lu2O3, ZrO2-Y2O3 TiO2, SG, Fe2O3, γ-AlO(OH) and C were used as catalyst supports, glycerol oxidation was carried out in the alkaline solutions and oxygen was used as oxidant. The optimal catalyst preparation parameters and glycerol oxidation conditions to obtain glyceric acid were determined. The best result (selectivity to glyceric acid 57% with glycerol conversion 92%) was achieved in the presence of 4.8%Pt/Al2O3 catalyst

Aerobic Oxidation of Xylose to Xylaric Acid in Water over Pt Catalysts

“…However, when xylose and glycolic acid or tartaric acid mixture was used as substrate, there are unconverted glycolic or tartaric acid in the solution, suggesting decarboxylation of tartaric acid or glycolic acid could be slow because of surface coverage by xylaric acid or xylonic acid. Prior studies on decarboxylation of glycerol over platinum and cobalt catalysts, or complete conversion oxalic acid to carbon dioxide on a platinum catalyst agree with our observation. On the basis of above discussion, we propose a plausible reaction pathway in Scheme .…”

Anisotropic growth of PtFe nanoclusters induced by lattice-mismatch: Efficient catalysts for oxidation of biopolyols to carboxylic acid derivatives

“…[10,28] The catalytic activities were compared for different catalysts based on TOF calculated for < 20% glycerol conversion and using Pt metal dispersion (% of surface to bulk Pt content, see Table S1 for details). As shown in Figure 3 (d 11,295.1±1841.9 h -1 , respectively), manifesting remarkable synergistic effects. Moreover, the tartronic acid yield (after 24 h) on bimetallic PtFe(1) and PtFe(1)-a catalysts is about 37−42%, much greater than values observed with monometallic Pt and Fe catalysts (3−14%).…”

“…Pt, Pd) often prevents further (oxidation) reactions. [11,12,28] The high tendency for decarboxylation or oxidative decarbonylation, due to strong interactions noted in the literature, is known to lead to significant side reactions such as CO formation and resultant catalyst poisoning at low temperature. [29] Clearly, the strong interaction demands higher activation energy for transformation of −C=O groups (in glyceraldehyde or glyceric acid molecules) on monometallic Pt catalyst surface (orange route in Figure 11).…”

“…Hydroxy dicarboxylic acids (HDCAs, such as tartronic acid, glucaric acid, and oxalic acid), derived from the oxidation of sugars and polyols, have high bio-activity and degradability in natural environments. [10][11][12] They are regarded as some of the most promising intermediates in polymer and pharmaceutical industries, and are currently manufactured from petrochemical feedstocks using corrosive/toxic reagents and severe operating conditions. [13][14][15] Among the challenges in HDCA synthesis are the difficulties in achieving high selectivity, elimination of stoichiometric reagents and avoidance of waste inorganic products.…”

Synergistic Effects of Bimetallic PtPd/TiO2 Nanocatalysts in Oxidation of Glucose to Glucaric Acid: Structure Dependent Activity and Selectivity

“…We also compared the glucose oxidation results of this work with reported glycerol (a C 3 sugar polyol) oxidation results over Pt-based catalysts. − In the cited studies on glycerol oxidation, poor liquid-phase carbon balance (67–85%) was reported when glycerol conversion was high (>30%, 50–90 °C). , This is because once the CO bond (i.e., carbonyl species) was formed from glycerol, decarbonylation catalyzed by noble metals led to a side reaction generating CO, which either deactivated the catalysts or formed CO 2 (in the form of carbonate salt) in the reaction medium. These products could not be quantitatively assessed by HPLC.…”