Avaliação da Permeabilidade de um Leito Catalítico de Paládio Disperso sobre Alumina para Hidrogenação Seletiva de MAPD em um Reator trickle-bed de uma Planta Petroquímica

Abstract

In the modeling of catalytic fixed bed reactors, for example, where the reaction mixture flows in liquid phase, the mass transport effects, time and energy are not properly represented if not considering the effects of the porous medium. The Reynolds number range to which to apply these models is limited, despite the existence of correlations to describe the dynamics of fluids in porous media (Darcy), and to predict permeability. Furthermore, there is dependence on various other parameters (particle size, porosity, fluid properties, etc.). In this context, this research aimed to experimentally determine the correlation between the permeability of a catalyst bed currently used in a trickle-bed reactor for selective hydrogenation of Methyl Acetylene and Propadiene (MAPD) ??in a petrochemical plant and the superficial velocity of the fluid in the porous medium in addition the porosity of the bed and its bulk density. The laboratory method used demineralized water percolating by a catalyst bed arranged in a glass tube partially immersed in a tub with water. Flow known water and hydraulic gradient (pressure difference) associated with the geometric characteristics of the bed allowed to obtain the information necessary for this study results suggest that the permeability is not invariant with the Reynolds number, revealing that the flow in porous media, the Reynolds number range investigated, is not darciniano. For the analysis system has been proposed a quadratic relation between the permeability and superficial velocity of the fluid. The values ??obtained in our laboratory for porosity (0,343) and bulk density of the bed (647.7 kg / m3) are close to the values ??expected by the manufacturer of the catalyst. DOI: 10.5935/1984-6835.20160081