An advanced (micro) kinetic modeling tool is presented. It can be used in the assessment of chemical kinetics going from power law models to full microkinetic models in terms of elementary steps. Reactants and products are considered to be present in a single, ideal aggregation state. Rate equations are automatically generated from the reaction network as specified by the user of the engine. Combined stochastic and deterministic algorithms are used for the optimization procedure. The flexibility of the code in its integration with different graphical userfriendly interfaces is illustrated. Thus, researchers with little programming skills can both implement advanced micro-kinetic models and perform their assessment.O-xylene hydrogenation data are used for illustration purposes.

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The gas-liquid mass transfer coefficients (MTCs) of a trickle bed reactor used for the study of benzene hydrogenation were investigated. The Ni/Al 2 O 3 catalyst bed was diluted with a coarse-grained inert carborundum (SiC) particle catalyst. Gasliquid mass transfer coefficients were estimated by using a heterogeneous model for reactor simulation, incorporating reaction kinetics, vapor-liquid equilibrium, and catalyst particle internal mass transfer apart from gas-liquid interface mass transfer. The effects of liquid axial dispersion and the catalyst wetting efficiency are shown to be negligible. Partial external mass transfer coefficients are correlated with gas superficial velocity, and comparison between them and those obtained from experiments conducted on a bed diluted with fine particles is also presented. On both sides of the gas-liquid interface the hydrogen mass transfer coefficient is higher than the corresponding benzene one and both increase significantly with gas velocity. The gas-side mass transfer limitations appear to be higher in the case of dilution with fine particles. On the liquid side, the mass transfer resistances are higher in the case of dilution with coarse inerts for gas velocities up to 3 · 10 -2 cm/sec, while for higher gas velocities this was inversed and higher mass transfer limitations were obtained for the beds diluted with fine inerts.