The variation of the supports on the Cu/SiO2 catalyst plays an important role in the catalytic performance for hydrogenation of dimethyl oxalate. The loss of silica in the form of tetramethoxysilane from the support under the reaction conditions is responsible for the deactivation of the Cu/SiO2 catalyst.

Introduction One-pot oxidation reaction consisted of direct synthesis of hydrogen peroxide (H2O2) from H2 and O2 gases and oxidation reaction using in situ generated H2O2 is promising synthetic method, because it is possible to use the unstable H2O2 immediately without isolation/purification steps, which would contribute to energy and time saving as well as avoid the risk of transportation of t...

A sample of MoOx/SiO2, in which all of the Mo cations are present as isolated mono-oxo molybdate moieties, was prepared and investigated to understand the redox chemistry of such molybdate species and their ability to exchange oxygen with O2 and H2O. Raman spectroscopy was used to monitor the exchange of 18O for 16O in the Mo=O bond of isolated molybdate species, whereas mass spectrometry was u...

A weak surface modification is applied to Co/SiO2 catalyst by hydrothermal treatment at 180°C for 5 h. Aluminum is introduced to Co/SiO2 catalysts during the surface modification. The effects of surface modification on Co/SiO2 catalyst are studied by changing the operating sequences of surface modification and cobalt impregnation in the catalyst preparation. Surface modification before cobalt i...

The presence of the heterogeneous mesoporous Al-MCM-41 catalyst remarkably accelerated the cyanosilylation of various aldehydes and ketones with trialkylsilyl cyanide, giving the corresponding cyanohydrin silyl ethers in quantitative yields under mild reaction conditions.

The aromatic rings of polystyrene (PS) were hydrogenated in decahydronaphthalene (DHN) expanded with supercritical carbon dioxide (scCO2). Conducting the hydrogenation in scCO2-DHN offers the benefits of improved transport properties, specifically lower solution viscosity and a higher PS diffusion coefficient. Various Pd catalysts are effective for hydrogenating the aromatic rings of PS at temp...

A silica-supported copper (Cu/SiO2) catalyst containing highly dispersed Cu nanoparticles was prepared via a crown-ether-assisted impregnation method. 12-crown-4-ether-assisted Cu/SiO2 outperformed several catalysts with various organic additives in the dehydrogenation of 2,3- and 1,4-butanediol. It found that catalytic activity, i.e., formation rate acetoin from 2,3-butanediol γ-butyrolactone ...

The effect of the different supports and catalyst-reducing agents on Fischer–Tropsch (FT) reaction was investigated. large surface area SiO2 support with a smaller pore volume deposited fine, evenly distributed Co3O4. Cubic-shaped Co3O4 appeared in clusters TiO2 support, whereas existed as single particles Al2O3 support. activity data obtained were discussed terms cluster size, particle shape, ...