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During steam injection processes, oil-soluble catalysts have demonstrated high efficiency by improving the flow properties of heavy crude oil into the reservoir. In order to gain a deeper understanding of the effect of this catalyst type and its reaction mechanism, further studies based on complex kinetic models are required. The catalytic effect of copper oleate on aquathermolysis of heavy crude oil was studied using experimental data obtained with a water/oil ratio of 3:7, a temperature range of 250 to 300 °C, and up to 72 h of reaction time. A kinetic model was developed to predict the yield of the SARA fractions and gases. The calculated kinetic parameters presented a proper fit concerning experimental data with average absolute error values lower than 4%. Results showed that copper oleate reduces the polyaddition reactions of heavy fractions, favoring the production of lighter compounds. A set of in-series and parallel reactions indicate that the reaction gas and aromatic compounds are mainly produced from the asphaltene fraction, where aromatic fractions subsequently generate saturates hydrocarbons.

Because of the growing world energy demand, biofuels obtained from the hydrotreatment of vegetable oils represent a renewable alternative to replace fossil fuels. The development of mathematical models is an accurate tool to design and simulate the performance of the reactor to predict product yields during the hydrotreatment of these oils. Better understanding of the different phenomena occurring during the hydrotreatment of vegetable oils and parameters influencing on this process by means of kinetic and reactor modeling is required. This was the motivation to develop an exhaustive review on different aspects of reaction kinetics, catalytic deactivation, and reactor modeling. Kinetics of model compounds and real feedstocks (oils) used to produce biofuels are analyzed and different assumptions for developing of reaction rate equations are discussed. It has been recognized that catalyst deactivation and reactor modeling must be deeply studied and supported with experimental data. There are few reported models that consider the mass transfer and temperature inside the catalytic particle. However, there are no models that consider the phase distribution and dispersion in the transient state, nor correlations to calculate the solubility of hydrogen in this type of system.

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Scaling up and validation of a trickle-bed reactor model were performed with the experimental information obtained during the hydrotreatment of vegetable oil in a pilot-scale reactor. The scale-up is carried out with a previously developed bench-scale reactor model that demonstrated good agreement with the experimental data. The differences in the characteristics of both reactor scales affected catalyst wetting efficiency, diffusion limitations inside the catalytic particle, and wall effects. These alterations were attributed mainly to the use of larger catalytic particles and higher surface velocities of the feedstock used in the pilot-scale reactor compared with the bench-scale reactor. In addition, the catalyst used in the pilot-scale reactor showed more effectiveness than that in the bench-scale reactor, thus presenting more triglyceride conversion. Simulations with the rector model also indicated that the higher feed flow rate and the large amount of catalyst used in the pilot-scale reactor generate a greater release of heat that makes it difficult to stabilize the reactor to reach steady state.