USE OF RTD AND LOCAL TRANSFER REPRESENTATION TO OBTAIN A TRANSIENT MODELLING OF A LIQUID-SOLID SYSTEM

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Modelling and simulation of a catalytic membrane reactor

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Gas-phase removal of hydrogen sulfide using iron oxyhydroxide at low temperature: Measurement of breakthrough curve and modeling of sulfidation mechanism

SSCI-VIDE+ECI2D+TYA:MTF:CGEInternational audienceWith the aim of removing hydrogen sulfide (H2S) from a gaseous phase around room temperature, we studied the performance of an iron oxyhydroxide (ferrihydrite) adsorbent by measuring a packed bed breakthrough curve (BTC) in a constant gas flow. We determined the amount of H2S adsorbed on the adsorbent by integrating BTCs measured under different experimental conditions. These conditions included the initial concentration of H2S, the superficial gas velocity and the temperature of the packed bed. Under the experimental conditions, it was found that the amount of H2S adsorbed was almost unchanged by the superficial gas velocity, whereas the adsorbed amount depended on the initial concentration of H2S and temperature. To solve the mass transfer equations in the packed bed, we developed a model considering such parameters as the kinetic constant of the sulfidation reaction, the intragranular diffusivity of H2S, and the number density of active sites on the adsorbent. By fitting the calculated BTC to the measured BTC under one of the experimental conditions, the set of parameters could be estimated. Using the same set of estimated parameters, we calculated the BTCs under the other experimental conditions. As a result we confirmed that the calculated BTC coincided with the BTC measured under a different initial H2S concentration and gas velocity. We also found that the number density of the active sites increased with increases in temperature. (C) 2014 Elsevier B.V. All rights reserved

Study of a platelet catalytic three-phase reactor filled with a Pt-β-SiC using formic acid oxidation as test reaction

International @ CDFA+TSN:MTF:PFOInternational audienceA platelet catalytic three-phase reactor equipped wit a Pt--SiC foam was characterized first in cold conditions (O2-water) with hydrodynamic of liquid phase and gas-liquid mass transfer. Axial dispersion was significant and dependant of operating conditions like interstitial velocities, foam morphology or flow direction as well as kLa in the range of 0.3 to 0.8.10-3 s-1. A specific protocol has been optimized to deposit Pt on the SiC foam. Intrinsic activity was determined and compare with other catalysts. Finally, platelet catalytic foam reactor was tested in continuous using acid formic oxidation as a model reaction. Reactor optimization has to be continued in order to avoid possible external mass transfer limitations

Methodology for the study of vacuum gas oil hydrocracking catalysts in a batch reactor

International @ RAFFINAGE+MTFInternational audienceNon

Study of a platelet catalytic three-phase reactor filled with a Pt-β-SiC using formic acid oxidation as test reaction

International @ CDFA+TSN:MTF:PFOInternational audienceA platelet catalytic three-phase reactor equipped wit a Pt--SiC foam was characterized first in cold conditions (O2-water) with hydrodynamic of liquid phase and gas-liquid mass transfer. Axial dispersion was significant and dependant of operating conditions like interstitial velocities, foam morphology or flow direction as well as kLa in the range of 0.3 to 0.8.10-3 s-1. A specific protocol has been optimized to deposit Pt on the SiC foam. Intrinsic activity was determined and compare with other catalysts. Finally, platelet catalytic foam reactor was tested in continuous using acid formic oxidation as a model reaction. Reactor optimization has to be continued in order to avoid possible external mass transfer limitations

Influence of slow diffusing species on mixture diffusion of hexane isomers in silicalite: Characterization by a new cyclic method

International audienceThe feasibility of mono- and di-branched paraffins separation on silicalite was evaluated by performing cyclic breakthrough experiments in liquid phase with mixtures of 2-methylpentane (2MP), 3-methylpentane (3MP), 2,3-dimethylbutane (23DMB), and 2,2-dimethylbutane (22DMB). For mixtures of the faster diffusing species (2MP, 3MP, and 23DMB), cyclic steady state is obtained from the first cycle. On the other hand, when the slow diffusing species 22DMB is involved, a slow accumulation occurs from cycle to cycle, yielding a change of the breakthrough curves for all the species. Using a diffusion model especially adapted to adsorbent saturation loading, the kinetic and thermodynamic parameters of 22DMB were estimated. Influence of the cycling conditions on the separation performance were finally studied by simulatio

Non-isothermal gas–liquid absorption with chemical reaction studies

International audienc

Consequence of structural identifiability properties on state-model formulation for linear inverse chromatography

International audienc