The construction of a computational framework that describes the kinetic details of the propylene oligomerization reaction network on Brønsted acidic zeolites is particularly challenging due to the considerable number of species and reaction steps involved in the mechanism. This work presents a detailed microkinetic model at the level of elementary steps that includes 4243 reactions and 909 ionic and molecular species within the C2–C9 carbon number range. An automated generation procedure using a set of eight reaction families was applied to construct the reaction network. The kinetic parameters for each elementary step were estimated using transition state theory, Evans–Polanyi relationships, and thermodynamic data. The reaction mechanism and its governing kinetic parameters were embedded into the design equation of a plug-flow reactor, which was the reactor configuration used to experimentally measure reactant and product concentrations as a function of propylene conversion and temperature on a representative H-ZSM-5 (MFI) zeolite. The resulting mechanistic model is able to accurately describe the experimental data over a wide range of operating conditions in the low propylene conversion (<4%) regime. The agreement between experimentally measured propylene conversion and product selectivities and the model results demonstrates the robustness of the model and the approach used to develop it to simulate the kinetic behavior of this complex reaction network.

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A general kinetic model has been developed to simulate the three-phase solvent-free hydrogenation of 2-methyl-3butyn-2-ol (MBY) over a commercial palladium-based catalyst. A Langmuir−Hinshelwood mechanism with noncompetitive adsorption between hydrogen and the organic species is assumed. Gas−liquid mass-transfer resistance is included in the model. Experiments were carried out in a stirred slurry reactor to estimate the kinetic parameters. The proposed model is able to predict the concentration profiles of the species involved during MBY hydrogenation, at varying temperatures (313−353 K), pressures (3.0−10.0 bar), and catalyst loadings (0.075−0.175 wt %). The model predictions were successfully validated using additional experimental runs conducted under different operating conditions and at a lower initial concentration of MBY.

The three-phase hydrogenation of 2-methyl-3-butyn-2-ol has been studied over a Pd/ZnO catalyst. A mathematical model has been proposed to predict the behavior of the system in the typical operating ranges if industrial reactors.

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In the frame of process development for the generation of chemical energy carriers, we studied the synthesis of methanol and formic acid from methyl formate hydrolysis in a continuous-flow millireactor. The aim was to establish the link between kinetics and phase behavior in the biphasic liquid regime. Reaction performance using the acidic ion-exchange resin Amberlyst 15 as catalyst was examined at various operating conditions such as space velocity, catalyst particle size, temperature, and initial reactant ratio. Results revealed substantially higher yields without mass transfer impediment with feed compositions exceeding methyl formate saturation in water. The simultaneous decrease in methyl formate and increase in polar product concentrations sufficed to bring the initially biphasic mixture to a homogeneous system as confirmed by thermodynamic UNIFAC equilibrium calculations. The separate analysis of effluent liquid phases unveiled a quasi-homogeneous catalytic process rooted in an aqueous layer at the resin surface, independent of the organic content. The fast and continuous synthesis of these chemicals constitutes a promising application for the development of direct fuel cells for portable power devices.

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Light alkanes from shale resources can potentially be converted to an easy-to-transport liquid hydrocarbon product by catalytic dehydrogenation followed by catalytic oligomerization. The chemical species in the liquid product and their concentrations depend on the process design, operating conditions, and choice of catalyst(s). In order to optimize process design and catalyst selection, it is important to be able to evaluate the economic value of the liquid product stream as a function of design variables and operating conditions. As an initial effort in addressing this challenge, the mixture octane number, a key property in determining the value of a gasoline blend stock, is considered. An approach is outlined for the estimation of the mixture octane number using a functional group contribution method and appropriate mixing rules, and this estimation procedure is interfaced with a microkinetic oligomerization reactor model. This combined microkinetic and octane number modeling approach is demonstrated using two case studies involving ethylene and propylene as feed streams, with product streams characterized in terms of octane number, molecular size distribution, and degree of branching. Results of this type are expected to provide guidance on catalyst development and process optimization.