Studying the internal mass transfer phenomena inside a Ni/Al2O3 catalyst for benzene hydrogenation

Metaxas, KC; Papayannakos, NG

dc.contributor.author	Metaxas, KC	en
dc.contributor.author	Papayannakos, NG	en
dc.date.accessioned	2014-03-01T01:29:16Z
dc.date.available	2014-03-01T01:29:16Z
dc.date.issued	2008	en
dc.identifier.issn	1385-8947	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19190
dc.subject	Benzene hydrogenation	en
dc.subject	Catalyst extrudates	en
dc.subject	Effectiveness factor	en
dc.subject	Intraparticle mass transfer	en
dc.subject	Tortuosity	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.other	Alumina	en
dc.subject.other	Benzene	en
dc.subject.other	Catalyst activity	en
dc.subject.other	Hydrogenation	en
dc.subject.other	Benzene hydrogenation	en
dc.subject.other	Catalyst extrudates	en
dc.subject.other	Effectiveness factor	en
dc.subject.other	Intraparticle mass transfer	en
dc.subject.other	Tortuosity	en
dc.subject.other	Mass transfer	en
dc.subject.other	Alumina	en
dc.subject.other	Benzene	en
dc.subject.other	Catalyst activity	en
dc.subject.other	Hydrogenation	en
dc.subject.other	Mass transfer	en
dc.title	Studying the internal mass transfer phenomena inside a Ni/Al2O3 catalyst for benzene hydrogenation	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.cej.2007.10.010	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.cej.2007.10.010	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	The mass transfer phenomena occurring inside Ni/Al2O3 catalytic extruidates have been studied for the liquid-phase hydrogenation of benzene. The experiments were conducted in a bench scale trickle-bed reactor at 17 bar absolute pressure and temperatures between 70 and 150 degrees C. Kinetic, thermodynamic and hydrodynamic effects have previously been examined [K.C. Metaxas, N.G. Papayarmakos, Ind. Eng. Chem. Res. 45(21) (2006) 7110-7119]. Temperature gradients inside the particle and across the liquid film surrounding catalyst particles have been checked and verified as absent. Concentration profiles of hydrogen and benzene show firstly that are consumed close to the surface of the extrudate and secondly to be in large excess along the particle radius. Catalyst particle tortuosity is estimated to be 3.75, very close to the value of 3.56 extracted from a statistical model based on nitrogen sorption hysteresis data. The effectiveness factor lies in the range of 0.19-0.35, implying strong diffusion limitations. The passivation of catalyst surface is posed as a solid reason for the modification of the true activation energy of the reaction occurred while moving from crushed catalyst particles to catalytic extruidates. (C) 2007 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE SA	en
heal.journalName	Chemical Engineering Journal	en
dc.identifier.doi	10.1016/j.cej.2007.10.010	en
dc.identifier.isi	ISI:000257260800038	en
dc.identifier.volume	140	en
dc.identifier.issue	1-3	en
dc.identifier.spage	352	en
dc.identifier.epage	357	en