Mathematical modeling of the generation of the secondary porous structure in a monolithic adsorbent

Monolithic adsorbent structures are of interest in pressure-swing adsorption due to its low pressure drop and mechanical stability in order to prevent attrition. We consider a monolithic adsorbent consisting of micro-porous zeolite particles embedded in a polyamide matrix. After the extrusion of a zeolite filled polyamide matrix a secondary structure of transport pores has to be formed in the polyamide phase to allow fast mass transport of the adsorbate to the zeolite particles. Here we develop a proof-of-the-concept mathematical model to describe the generation of the macro-porous structure in a zeolite–polyamide–wax system. The mathematical model is based on the discrete element method (DEM). We demonstrate that the problem of evolution of a complex morphology can be modeled by the DEM model. Systematic parametric studies provide us with the qualitative guidance on the effects of processing parameters and the initial distribution of polyamide and wax phases on the final morphology of the monolithic adsorbent.