Methodology of gas adsorption process design. Separation of propane propylene and n/iso-paraffins mixtures

The general guidelines for developing a gas separation process based on ads orption are reviewed. Two important industrial cases based on adsorption pr ocesses are selected: the separation of propane/propylene mixtures and n/is o-paraffins mixtures. The 13X zeolite and Ag+-Amberlyst were used as adsorb ent for propane/propylene mixture taking into account information from the open literature. The 5A zeolite was selected for n/iso-paraffins system; th e adsorption equilibrium and diffusivity data were obtained from gravimetri c and ZLC techniques respectively. A mathematical model for the bulk separa tion in fixed bed upon non-isothermal non-adiabatic conditions is formulate d and solved numerically. The simulated results are compared with the avail able experimental breakthrough curves. Finally, a cyclic process based in t he PSA-VSA and TSA concepts is proposed for these systems.