Determination of styrene hydrogenation surface kinetics through detailed simulation of the hydrogen uptake curve

• Published in: Reaction chemistry & engineering Vol. 4; no. 8; pp. 1477 - 1485
• Main Authors: Stamatiou, Ilias, Brennan, Colin, Muller, Frans L
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 01.08.2019
• Subjects: Adsorption; Catalysis; Catalysts; Chemical reactions; Computer simulation; Ethylbenzene; Hydrogen storage; Hydrogenation; Mass transfer; Organic chemistry; Parameter estimation; Reaction kinetics; Styrenes; Surface chemistry; Surface kinetics
• ISSN: 2058-9883; 2058-9883
• DOI: 10.1039/c8re00132d

The styrene hydrogenation over Pd/C in a three-phase dead-end stirred tank reactor has been simulated. The mass transfer coefficients were calculated based on experimental data. The fast intrinsic reaction kinetics did not allow the effects of the gas-liquid and liquid-solid mass transfer to be ignored. A rigorous model is described which includes all mass transfer steps with a Langmuir-Hinshelwood model of the surface chemical reaction. The adsorption constants of hydrogen, styrene and ethylbenzene on catalyst active sites were estimated from a single experimental reaction profile. The parameterised model was validated against 6 further sets of experimental data which were not included in the parameters' estimation procedure. Results indicate the ethylbenzene, styrene and hydrogen adsorption to have an equilibrium constant of 148.34 L mol −1 , 847.72 L mol −1 and 19 984 L mol −1 , respectively. The intrinsic rate constant for the 4.63% Pd/C catalyst is 0.0542 mol g cat −1 s or 1.17 mol g Pd −1 s −1 . This work demonstrates that the analysis of the whole hydrogenation reaction profile in combination with detailed mass transfer resistance evaluation can provide fundamental system properties. The styrene hydrogenation over Pd/C in a three-phase dead-end stirred tank reactor has been simulated without neglecting the mass transfer effects.