Melaz Tayakout-Fayolle

Non-isothermal gas-liquid absorption with chemical reaction studies. Temperature measurements of a spherical laminar film surface and comparison with a model for the CO2/NaOH system

The present work deals with the temperature measurements of a thin spherical liquid film surface during non-isothermal absorption with chemical reaction. The absorption of CO2 into aqueous NaOH solutions has been used to test the proposed technique. The measurement is based on the use of an infrared pyrometer through a ZnSe window. The experimental results are compared to calculated values obtained from a previously described non-isothermal model. The measured and computed values of the flux of absorbed gas and the temperature profiles are very close without performing any parameter adjustment. The highest measured temperature increase is about 5 K, and despite this low thermal effect, the system has proved to be highly sensitive.

Kinetic parameter estimation and modelling of sucrose esters synthesis without solvent

Abstract In this paper, a kinetic model for the synthesis of the sucrose esters without solvent is developed. This synthesis is a heterogeneous reaction between the sucrose (solid) and the methyl palmitate (liquid) in the presence of a solid catalyst. We have established the kinetic model by steps, by first considering a homogeneous model and then by taking into account the heterogeneity of the medium. Thus, we have assumed additional steps in the model corresponding to the activation of the solid sucrose by the catalyst and autocatalytic steps. This activation parameter is associated to the viscosity of the medium. As a consequence of these observations, the study of the sensibility and the accuracy of the parameters allowed us to simplify the model.

Methodology for the Study of Vacuum Gas Oil Hydrocracking Catalysts in a Batch Reactor – Coupling of GC-2D Data with Vapour-Liquid Equilibrium

A new approach for studying complex feedstock conversion with a hydrocracking catalyst is proposed in this work. The reaction was carried out in a batch reactor. Vapor and liquid samples were taken at different reaction times, both at operating conditions and after cooling to room temperature. Two-dimensional gas chromatography was used to characterize in detail the composition of condensed vapor and of liquid phases, while gas samples were analyzed by conventional gas chromatography. From room temperature conditions data, vapor fraction of the hydrocarbon mixture and compositions of each phase at reaction condition were calculated and validated. Following this methodology then allows a simple tracking technique for the study of complex hydrocarbon mixture reactions in liquid and vapor phases.

Composite zeolite membranes characterization by using a transient state experimental technique and a parameter estimation procedure

We describe a non-destructive transient state method for the determination of thermodynamic and transport properties of zeolite composite membranes. The properties under consideration are included as parameters of a linear dynamic model of the membrane. The parameters values are obtained thanks to an estimation procedure based on the comparison between simulated and measurements realized in the linear domain. A step-by-step experimental procedure is derived from a structural identifiability analysis of a simplified linear model of the membrane. A more detailed linear model is then used for the estimation procedure. Due to its transient nature, this technique allows the zeolite selective layer effective thickness determination as well as that of thermodynanic and transport properties of sorbing hydrocarbons. Some examples of results are given to illustrate the capabilities of the technique.