The vapor-phase selective oxidation of propylene (H2C CHCH3) to acrolein (H2C CHCHO) was investigated over supported V2O5/Nb2O5 catalysts. The catalysts were synthesized by incipient wetness impregnation of V-isopropoxide/isopropanol solutions and calcination at 450 8C. The catalytic active vanadia component was shown by in situ Raman spectroscopy to be 100% dispersed as surface VOx species on ...

Gas-phase ion chemistry methods that capture and characterize the degree of activation of small molecules in the active sites of homogeneous catalysts form a powerful new tool to unravel how ligand environments affect reactivity. A key roadblock in this development, however, is the ability to generate the fragile metal oxidation states that are essential for catalytic activity. Here we demonstr...

Iridium is very important element among the all transition metals with highest reported oxidation state i.e. +9 in gas phase existing species IrO4. Instead of its less reactivity, it forms number of compounds having oxidation states between -3 to +9. It is second known densest element after osmium. Till now its toxicity and environmental impact is not much more reported and thus it may be use a...

The selective catalytic oxidation (SCO) of gas phase ammonia (NH3) to nitrogen and water has been proposed as an effective ammonia removal process. This study reports that the oxidation of NH3 with oxygen to form N2 was investigated by SCO using a Pt-Rh complex catalyst that was synthesized by the incipient wetness impregnation process. The catalysts were performed using fluorescent spectroscop...

catalysts with the formula of laco(1+x)o(3+δ), where 0 ≤ x ≤ 1, were studied for oxidation of co and c2h6 in a synthetic exhaust gas, comprising 6.0 % co and 0.2 % c2h6 in ar. ethane was selected as a model for hydrocarbons in the exhaust gas. the performance of catalysts is correlated to their properties, particularly their redox in oxidizing and reducing atmospheres. xrd patterns show perovsk...

The interactions between oxygen permeation and homogeneous fuel oxidation reactions on the sweep side of an ion transport membrane (ITM) are examined using a comprehensive model, which couples the dependency of the oxygen permeation rate on the membrane surface conditions and detailed chemistry and transport in the vicinity of the membrane. We assume that the membrane surface is not catalytic t...

Catalytic ignition of CH4, CO, and H2 oxidation on platinum and palladium at atmospheric pressure is studied numerically. Two simple configurations are simulated: the stagnation flow field over a catalytically active foil and a chemical reactor with a catalytically active wire inside. The simulation includes detailed reaction mechanisms for the gas phase and for the surface. The gas-phase trans...

Abstract Methane (CH 4 ) is the primary component of natural gas and a powerful greenhouse gas. CH can be utilized as an important raw material to produce value‐added chemicals via catalytic partial oxidation, oxidative/non‐oxidative coupling, steam reforming, dry etc. Redox potential key thermodynamic quantity in these processes while currently, only standard reduction potentials at 25°C 1 atm...

Bromine gas was evaluated for converting elemental mercury (Hg0) to oxidized mercury, a form that can readily be captured by the existing air pollution control device. The gas-phase oxidation rates of Hg0 by Br2 decreased with increasing temperatures. SO2, CO, HCl, and H2O had insignificant effect, while NO exhibited a reverse course of effect on the Hg0 oxidation: promotion at low NO concentra...

Perovskite-type oxides of LaFe(1+x)O(3+δ) (x = 0.0, 0.2, 0.5 and 0.7) were synthesized by citrate sol–gel methodto ensure the formation of nanosized perovskites. The physicochemical properties of these LaFe(1+x)O(3+δ)materials were characterized by thermal gravimetric/differential analyses, Fourier transform infraredspectroscopy, X-ray powder diffraction, scanning electron and...