Catalytic hydrogenation of benzene and toluene

Abstract

The reaction takes Place in liquid phase in a batch reactor, at temperature between 393 K and 433 K. Partial hydrogen pressure is varied between 1.1 MPa and 3.0 MPa. Catalytic activity is expressed in mol of aromatic compund which react per gram of catalyst and per second. The general mechanism proposed for this kind of reaction assumes that there is no competitive adsorption between the aromatic compound and hydrogen. Reaction occurs between two molecules that are absorbed on two different sites. The kinetic model which describes the hydrogenation process of aromatic compounds in liquid phase is the following:

Activation energy and adsorption heat increase with the increase of the number of substituents, and with length of the chain in the benzene ring, while reaction velocity decreases.