0021-9517/$ see front matter 2010 Elsevier Inc. A doi:10.1016/j.jcat.2010.06.017 * Corresponding author. Fax: +1 510 642 4778. E-mail address: [email protected] (A.T. Bel A novel approach is described for preparing Ga-promoted Pt particles for the dehydrogenation of light alkanes to alkenes. The modifying element, Ga, was introduced by transference from the support, a calcined Mg(Ga)(Al)O...

The adsorption of propylene on clean and hydrogen-covered Pd(1 1 1) has been studied by using temperatureprogrammed desorption (TPD) and reflection-absorption infrared spectroscopy. Propylene adsorbs in a di-r configuration on clean Pd(1 1 1). At high exposures, it forms second and subsequent layers. Upon heating, propylene desorbs molecularly at 200 and 280 K and, in contrast to ethylene adsor...

Ceria (CeO2 ) supports are unique in their ability to trap ionic platinum (Pt), providing exceptional stability for isolated single atoms of Pt. The reactivity and stability of single-atom Pt species was explored for the industrially important light alkane dehydrogenation reaction. The single-atom Pt/CeO2 catalysts are stable during propane dehydrogenation, but are not selective for propylene. ...

The alkylation of benzene by propane to yield isopropylbenzene (iPrPh) was studied using bifunctional Pd-acid catalysts, such as Pd-heteropoly acid and Pd-zeolite, in a fixed bed reactor at 300 ◦C and 1 bar pressure. Keggin-type tungstosilicic acid H4SiW12O40 (HSiW) and zeolite HZSM-5 were used as the acid components in these catalysts. The reaction occurred most efficiently over 2%Pd/25%HSiW/S...

Zr-based metal-organic frameworks (MOFs) have been shown to be excellent catalyst supports in heterogeneous catalysis due to their exceptional stability. Additionally, their crystalline nature affords the opportunity for molecular level characterization of both the support and the catalytically active site, facilitating mechanistic investigations of the catalytic process. We describe herein the...

Introduction SAPO-34 is a silicoaluminophosphate zeolite with 8-membered ring windows (~0.38nm) displaying chabazite structure. SAPO-34 is an efficient catalyst showing improved catalytic performance in reactions such as methanol conversion to olefins [1], oxidative dehydrogenation of propane [2], conversion of light alkenes [3]. Its catalytic properties are mainly attributed to its mild acidit...

Propylene is an important raw material for the production of many valuable compounds, especially polypropylene, consumption which continues to grow every year. The reaction oxidative dehydrogenation propane, where carbon dioxide used as a mild oxidant, promising method producing propylene. At same time, problem utilization greenhouse gas CO2 partially solved. synthesis and analysis physicochemi...

In situ diffuse reflectance UV-visible spectroscopy was used to measure the dynamics of catalyst reduction and oxidation during propane oxidative dehydrogenation (ODH) on VOx/gamma-Al2O3. Transients in UV-visible intensity in the near-edge region were analyzed using a mechanistic model of ODH reactions. Rate constants per site for the kinetically relevant reduction step (C-H bond activation) me...

Highly dispersed molybdenum oxide supported on mesoporous silica SBA-15 has been prepared by anion exchange resulting in a series of catalysts with changing Mo densities (0.2-2.5 Mo atoms nm(-2) ). X-ray absorption, UV/Vis, Raman, and IR spectroscopy indicate that doubly anchored tetrahedral dioxo MoO4 units are the major surface species at all loadings. Higher reducibility at loadings close to...

Platinum-based bimetallic nanoparticles are analyzed by the application of density functional theory to a series of tetrahedral Pt3X cluster models, with element X taken from the P-block, preferably group 14, or from the D-block around group 10. Almost identical cluster geometries allow a systematic investigation of electronic effects induced by different elements X. Choosing the propane-to-pro...