603 research outputs found
Analysis of elementary surface reactions in aromatic hydrogenation on Pt using Single-Event MicroKinetics
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Microkinetic Model Construction as a Route towards a Better Understanding of Chemical Processes
Experimental investigation of ethylene hydroformylation to propanol on Rh and Co based catalysts
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Ethylene oligomerization on bifunctional heterogeneous catalysts: model development and catalyst optimization
Extension of the single-event microkinetic model to alkyl substituted monoaromatics hydrogenation on a Pt catalyst
The Single-Event Micro Kinetic (SEMK) methodology, which had been successfully applied to benzene hydrogenation on a Pt catalyst, has now been extended toward substituted monoaromatics, that is, toluene and o-xylene. The single event concept Combined with thermodynamic constraints. allowed to significantly reduce the number of adjustable parameters. In addition to the number of unsaturated nearest neighbor carbon atoms, H-atom addition rate and equilibrium coefficients were assumed to depend on the carbon atom type, that is, secondary or tertiary. This leads to three additional :reaction families compared to benzene hydrogenation: Gas. phase toluene and o-xylene hydrogenation experiments were performed on 0.5 wt % Pt/ZSM-22 in a temperature range from 423 to 498 K, a total pressure range from 1 to 3 MPa, H-2 inlet partial pressures between 100 and 600 kPa and aromatic inlet partial pressures between 10 and 60 kPa. A simultaneous regression of the :SEMK,Model to an experimental data set consisting of 39 toluene and 37 o-xylene hydrogenation experiments resulted in activation energies of H additions to tertiary:carbon:atoms:that are 10.5 kJ mol(-1) higher than to secondary carbon atoms. This can be related to the steric hindrance experienced during H addition to a carbon atom bearing a substituent. The presence of a substituent on the aromatic king was found not to affect the Chemisorption enthalpies. The reaction path analysis has been carried out via differential contribution analysis and identified that the hydrogenation first, occurs at secondary carbon atoms, prior to the hydrogenation of the tertiary carbon atoms in the hydrogenation Sequence. This is in line with the distribution of hydrocarbon species on the catalyst surfac
Towards an optimal ethylene oligomerization catalyst based on single-event microkinetic modelling
From ideal gas to relevant three-phase conditions in hydrodenitrogenation reactions and reactors
From fundamental insights to economic viability: recovering natural products from deodorizer distillates
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Anisole hydrodeoxygenation over supported CoMo catalysts: effect of Co/Mo ratio and support on catalyst stability and activity
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