Supported molybdenum carbide (yMo2C/M41) and Cu-promoted molybdenum carbide, using a mechanical mixing and co-impregnation method (xCuyMo2C/M41-M and xCuyMo2C/M41-I) on a mesoporous molecular sieve MCM-41, were prepared by temperature-programmed carburization method in a CO/H2 atmosphere at 1073 K, and their catalytic performances were tested for CO2 hydrogenation to form methanol. Both catalys...

A unique cooperative H2 activation reaction by heterobimetallic (NHC)M'-MCp(CO)2 complexes (NHC = N-heterocyclic carbene, M' = Cu or Ag, M = Fe or Ru) has been leveraged to develop a catalytic alkyne semi-hydrogenation transformation. The optimal Ag-Ru catalyst gives high selectivity for converting alkynes to E-alkenes, a rare selectivity mode for reduction reactions with H2. The transformation...

A novel type of high-pressure membrane reactor has been developed for hydrogenation in supercritical carbon dioxide (scCO(2)). The main objectives of the design of the reactor are the separate feeding of hydrogen and substrate in scCO(2) for safe reactions in a continuous flow process, and to reduce the reaction time. By using this new reactor, hydrogenation of cinnamaldehyde into hydrocinnamal...

In-situ synthesis of a zeolite with encapsulated Pt was conducted to prepare a sulfur-resistant noble metal catalyst based on concepts of shape selectivity and hydrogen spillover. The prepared zeolite was of the sodalite type, in which the pore openings allow H2 to enter the pores but not H2S. Chemisorption with H2/CO was conducted to verify the most of Pt atoms distribution in the cage of Pt/S...

Abstract The study investigates hydrogenation of CO 2 over mono- and bimetallic catalysts supported on biochar. In this reaction, iron–cobalt were shown to surpass monometallic iron cobalt in terms catalytic performance. optimal combination performance parameters was reached at an ratio 3 : 1. composition genesis the active phase Fe–Co catalyst identified, mechanism suggested for iron-dominated...

Hydroformylation of cyclohexene was studied with a catalyst system of Ru3(CO)12 and LiCl using H2 and CO2 instead of CO in NMP. The influence of H2 and CO2 pressures on the total conversion and the product distribution was examined. It was shown that increasing total pressure of H2 and CO2 promoted the reverse water gas shift reaction and increased the yield of cyclohexanecarboxaldehyde. Its hy...

In this contribution, we report the successful preparation of supported metal catalysts using dendrimer-encapsulated Pt nanoparticles as metal precursors. Polyamidoamine (PAMAM) dendrimers were first used to template and stabilize Pt nanoparticles prepared in solution. These dendrimer-encapsulated nanoparticles were then deposited onto a commercial high surface area silica support and thermally...

A small amount of coadsorbed impurity species could significantly alter the surface diffusion of CO on Ni~110!. Three impurity species, sulfur, oxygen, and potassium are studied here. The former two are known as ‘‘poisons’’ and the latter as a ‘‘promoter’’ for CO hydrogenation on Ni. All three are found to impede CO diffusion drastically. The apparent diffusion activation energy ED increases fr...

Bilayer Mg/Co thin films prepared using thermal evaporation method at pressure 10 – 5 torr at room temperature. The films were rapid thermal annealed (RTA) using halogen lamp for different times to get a homogeneous structure of Mg/Co thin films. The hydrogen gas was introduced in hydrogen chamber, where samples were kept at different pressure of H2 for thirty minutes. The UV–VIS transmission s...

The reaction mechanism of CO₂ hydrogenation catalyzed by [FeH(PP₃)]BF₄ (PP₃ = P(CH₂CH₂PPh₂)₃) had been investigated by DFT calculations. Our calculations indicated that the reduction of carbon dioxide could be carried out via two spin states, the high-spin (HS) triplet state and the low-spin (LS) singlet state. The minimum energy crossing points (MECPs) on the seam of two intersecting PESs (pot...