fischer-tropsch catalysts with high activity and selectivity for olefins were produced using mordenite type sio2/al2o3= 12, 20, 28, 62 zeolite supported iron carbonyl compounds and were characterized by x-ray powder diffraction. the adsorptionof volatile fe(co)5 on the support surface was carried out under vacuum at room temperature. reduction les were monitored by vibrating sample magnetometer...

A series of constrained geometry O-functionalized cyclopentadienylchromium complexes (1-6) and a S-functionalized cyclopentadienylchromium complex (7) were first synthesized, characterized, and tested as catalyst precursors for the olefin polymerization. In the presence of MAO, the complexes exhibited high catalytic activity for the polymerization of ethylene. It is shown that ligand variations...

In this work, the early degradation step of the pyrolysis of some polymers in the presence of certain catalysts has been studied using thermogravimetric analysis (TGA). Three commercial polymers (PE, PP and EVA) and three catalysts were studied (ZSM-5, MCM-41a, and MCM-41b), and the MCM-41a catalyst has been selected for the analysis of the earlier steps of the pyrolysis process carried out in ...

This study explores a facile method to prepare an efficient and durable support for Pt catalyst of polymer electrolyte membrane fuel cell (PEMFC). As a candidate, Nb-doped TiO2 (Nb-TiO2) nanofibers are simply fabricated using an electrospinning technique, followed by a heat treatment. Doping Nb into the TiO2 nanofibers leads to a drastic increase in electrical conductivity with doping level of ...

The paper relates to a catalyst, comprising copperchromium spinel, coated on carrier γ-Al2O3. The effect of preparation conditions on the active component composition and activity behavior of the catalysts is discussed. It was found that the activity of carbon monoxide, DME, formaldehyde and methanol oxidation reaches a maximum at an active component content of 20 – 30 wt. %. Temperature calcin...

A synergistic graphene-based catalyst was engineered by the in situ growth of "naked" Au-nanoparticles (NPs) on graphene sheets. The catalyst exhibits excellent switchable peroxidase-like activity in response to specific DNA.

The activity and selectivity of aluminaand magnesia-supported vanadia for propane oxidative dehydrogenation can be enhanced by can be enhanced by interactions of vanadia with molydena for the alumina-supported catalyst and by phosphorous doping for the magnesia-supported catalyst.

An extremely efficient catalytic protocol for the synthesis of spirooxindole derivatives via a one-pot three component approach in the presence of SBA-Oxime-Zn, as a heterogeneous catalyst using water as a green solvent is reported. The catalyst exhibited excellent catalytic activity, and the proposed methodology is capable of providing the desired products in good yield and short reaction time...

A simple and feasible contact mode called gravitational contact mode (GCM) was developed for the first time to imitate the practical state between soot and catalyst. By simulating rainwater adsorption on a lawn in nature, we synthesized a lawn-like CuO nanorods array, which exhibited rather good catalytic activity for diesel soot combustion under GCM. Moreover, the CuO nanorods array could serv...

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...