34067-76-0Relevant articles and documents
Influence of Dioxygen on the Promotional Effect of Bi during Pt-Catalyzed Oxidation of 1,6-Hexanediol
Xie, Jiahan,Huang, Benjamin,Yin, Kehua,Pham, Hien N.,Unocic, Raymond R.,Datye, Abhaya K.,Davis, Robert J.
, p. 4206 - 4217 (2016/07/12)
A series of carbon-supported, Bi-promoted Pt catalysts with various Bi/Pt atomic ratios was prepared by selectively depositing Bi on Pt nanoparticles. The catalysts were evaluated for 1,6-hexanediol oxidation activity in aqueous solvent under different dioxygen pressures. The rate of diol oxidation on the basis of Pt loading over a Bi-promoted catalyst was 3 times faster than that of an unpromoted Pt catalyst under 0.02 MPa of O2, whereas the unpromoted catalyst was more active than the promoted catalyst under 1 MPa of O2. After liquid-phase catalyst pretreatment and 1,6-hexanediol oxidation, migration of Bi on the carbon support was observed. The reaction order in O2 was 0 over Bi-promoted Pt/C in comparison to 0.75 over unpromoted Pt/C in the range of 0.02-0.2 MPa of O2. Under low O2 pressure, rate measurements in D2O instead of H2O solvent revealed a moderate kinetic isotope effect (rateH2O/rateD2O) on 1,6-hexanediol oxidation over Pt/C (KIE = 1.4), whereas a negligible effect was observed on Bi-Pt/C (KIE = 0.9), indicating that the promotional effect of Bi could be related to the formation of surface hydroxyl groups from the reaction of dioxygen and water. No significant change in product distribution or catalyst stability was observed with Bi promotion, regardless of the dioxygen pressure.
Perspectives on the kinetics of diol oxidation over supported platinum catalysts in aqueous solution
Ide, Matthew S.,Davis, Robert J.
, p. 50 - 59 (2014/01/06)
The catalytic oxidation of a variety of terminal alcohols was performed over Pt/C with 10 bar dioxygen at 343 K in aqueous solvent at low pH. The influences of Pt particle size, carbon support, alcohol structure, and start-up conditions were explored. Although the turnover frequency was not affected by particle size or the carbon support, the structure of the alcohols affected their initial rate of conversion. Both the rate of oxidation of α,ω-diols and selectivity of the diols to the diacids increased with increasing carbon chain length. The rate of 1,6-hexanediol oxidation was independent of dioxygen pressure and the order of reaction with respect to diol concentration depended on the start-up conditions. A kinetic model involving two types of metal sites was proposed to account for the experimental observations.
METHOD FOR PRODUCING LACTONES FROM DIOLS
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Page/Page column 4, (2010/12/29)
The present invention provides a process for preparing lactones from optionally substituted, saturated aliphatic diols having from five to 20 carbon atoms between the two ring-closing hydroxyl groups by catalytic dehydrogenation and cyclization in the liquid phase over at least one catalyst.
