the kinetics of catalyst deactivation and coke formation during dehydrogenation of propane over supported pt–based catalysts and, in particular, the effect of alkali metal promoters on catalyst activity and stability were studied. the analysis of propane conversion data showed that there is an optimum level of alkali metal promoter loading for both catalyst activity and stability.a model based ...

The kinetics of catalyst deactivation and coke formation during dehydrogenation of propane over supported Pt–based catalysts and, in particular, the effect of alkali metal promoters on catalyst activity and stability were studied. The analysis of propane conversion data showed that there is an optimum level of alkali metal promoter loading for both catalyst activity and stability.A model ba...

The run length of cracking furnaces is limited by the formation of coke on the internal skin of the reactor tubes. The reaction mechanism of thermal cracking of hydrocarbons is generally accepted as free-radical chain reactions. On the basis of the plant output data and the insight in the mechanisms for coke formation in pyrolysis reactors, a kinetic model describing the coke formation has been...

The active cooling of the Supersonic Combustion Ramjet engine, for hypersonic flight purpose, is ensured thanks to fuel, n-dodecane for the present study. The endothermic fuel pyrolysis, starting above 800 K, could generate an unwanted coke formation. Experimental tests up to 1125 K and between 1 MPa and 6 MPa have been performed on the hydrocarbon fuel pyrolysis to evaluate the coking activity...

Nickel nanoparticles (Ni NPs) are quite interesting because they exhibit high catalytic activity, high selectivity and high efficiency in fuel cells [1, 2]. However the coke-formation takes place in these NPs involving chemical reactions. For instance the CO2 reforming of methane gas in the presence of Ni NPs leads to the formation of coke containing predominantly the carbon nanotubes (CNTs) [3...

The catalytic activity of large zeolite H-ZSM-5 crystals in methanol (MTO) and ethanol-to-olefins (ETO) conversions was investigated and, using operando UV/Vis measurements, the catalytic activity and deactivation was correlated with the formation of coke. These findings were related to in situ single crystal UV/Vis and confocal fluorescence micro-spectroscopy, allowing the observation of the s...

The influence of catalyst support alumina-silica in terms of different Al2O3 to SiO2 mole ratios containing 20 wt.% Ni on the production of hydrogen and catalyst coke formation from the pyrolysis-catalysis of waste tyres is reported. A two-stage reactor system was used with pyrolysis of the tyres followed by catalytic reaction. There was only a small difference in the total gas yield and hydrog...

Fluidized bed was employed to investigate propane steam reforming over Ni-K/CeO2-Al2O3 catalyst. The catalyst was characterized by XRD, SEM, TG/DTA, and N2 adsorption-desorption tests. Effects of promoters, space velocity, temperature, and steam/propane (S/C) ratio on propane conversion, H2 yield, H2/CO ratio, and stability were studied and discussed. The experiments were carried out under cond...