Glycerol Oxidation with Oxygen over Bimetallic Pt-Bi Catalysts under Atmospheric Pressure

Factors affecting activity and selectivity in the oxidation of glycerol promoted by platinum catalysts

“…The top-left panel shows the accumulation of the different products detected in our batch reactor, plotted in the form of turnover numbers (TONs), expressed in units of glycerol molecules consumed per number of platinum surface atoms in the catalyst (estimated using the Pt nanoparticle size distributions obtained from TEM measurements), versus time. The initial overall TOF in this catalytic run is about 40 min −1 , a value quite a bit higher than those seen with supported Pt catalysts in other reports [15][16][17][18]20,27,29,31 and also competitive with some Bimodified samples 15,16 (Table 1). Only three main products were seen in our kinetic runs, GLYALD, DHA, and GLA; no other compounds were detected within the detection limits of our experiments.…”

“…[6][7][8] It has been repeatedly shown that selectivity toward the oxidation of the secondary alcohol group can be enhanced by the addition of Bi to Pt catalysts, 6,[8][9][10][11][12][13][14][15][16][17] but the catalytic performance also varies significantly when using acidic versus basic media, 3,7,11,18 and only limited research has been carried out under neutral conditions. However, the published research in this area is sometimes confusing and not conclusive in terms of how to select the best catalysts for each individual application.…”

“…However, the published research in this area is sometimes confusing and not conclusive in terms of how to select the best catalysts for each individual application. 23,24 Many other parameters related to the characteristics of the catalyst as well as the operating conditions have been shown to influence the activity and selectivity of glycerol oxidation, including the nature of the support, 20,25,26 which often is a form of activated carbon, 6,10,19,27 the catalyst preparation method, 16,18 the metal loading, particle size, and particle shape, 13,17,22,28,29 the type of reactor used, 9 and the reaction conditions, including temperature and oxygen pressure. [6][7][8] It has been repeatedly shown that selectivity toward the oxidation of the secondary alcohol group can be enhanced by the addition of Bi to Pt catalysts, 6,[8][9][10][11][12][13][14][15][16][17] but the catalytic performance also varies significantly when using acidic versus basic media, 3,7,11,18 and only limited research has been carried out under neutral conditions.…”

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

“…14 For gold catalysts, many supports have been investigated, i.e., carbon materials, several metal oxides and polymers. 1,8,[23][24][25] Since 1993, when Kimura et al 17 reported glycerol oxidation over Pt/C, mainly carbon material supports have been studied for monometallic Pt catalysts, i.e., activated carbon, graphite and MWNT. [17][18][19] Liang et al 6 reported that multi-wall carbon nanotubes (MWNT)-supported Pt catalysts were more active and selective than Pt/activated carbon (AC) catalysts, but this type of support is expensive and the preparation of catalyst is complicated, so in further studies, the authors returned to activated carbon.…”

“…3,9,11 Most of the studies concerning the heterogeneous oxidation of glycerol were dedicated to the selective oxidation of glycerol over supported gold catalysts using oxygen as the oxidant. 1,8,[23][24][25] Since 1993, when Kimura et al 17 reported glycerol oxidation over Pt/C, mainly carbon material supports have been studied for monometallic Pt catalysts, i.e., activated carbon, graphite and MWNT. Using an Au/C catalyst, Carretin et al reported a selectivity to glyceric acid of 100 % at a glycerol conversion of 56 %.…”