MULTICOMPONENT TRANSPORT OF HYDROCARBONS IN FCC CATALYST

ÁVILA, ADOLFO; BIDABEHERE, CLAUDIA; SEDRAN, ULISES

Buenos Aires-Argentina

Congreso; XXII INTERAMERICAN CONGRESS OF CHEMICAL ENGINEERING; 2006

AAIQ - Asociación Argentina de Ingenieros Químicos

The transport properties of simple mixtures of hydrocarbons in a commercial FCC catalyst are studied. The experimental information was obtained from unsteady state adsorption processes with a ternary mixture of hexane, decane and toluene and a binary mixture of hexane and 1-hexene at 250ºC. The calculus of adsorbate concentrations and comparison of mixture adsorption selectivities with individual adsorption behavior of the hydrocarbons on the catalyst allows to evaluate the effect on overall transport from species with stronger individual adsorption. The mixture transport behavior is simulated by a proposed model based in the Maxwell – Stefan formulation in combination with an isotherm according to the ideal adsorbed solution theory (IAST). The predictions of the apparent selectivities were closed to the experimental values and higher than those calculated for diluted conditions. Interactions within zeolite particles contribute positively to C10 overall transport in comparison to the rest of hydrocarbons in the mixture (TOL and C6). Similar behavior is observed in the case of the olefin related to paraffin in the hexane/1-hexene mixture