SAPO-34 assisted C3 separation: Modeling and simulation

Chabazite (CHA) framework type SAPO-34 molecular sieve has been synthesized and its C3 (propane/propylene) uptake potential was evaluated in the temperature range of 303-323 K by measuring equilibrium and kinetic adsorption data using volumetric/gravimetric adsorption measurement technique. The measured data were analyzed by Langmuir-Freundlich isotherm model and Crank's equation respectively to estimate adsorption capacities, diffusivities and diffusion activation energies for C3 hydrocarbons. The estimated diffusivity data suggested a high kinetic selectivity for propylene over propane on SAPO-34 framework. A Wicke-Kallenbach cell for propane/propylene separation over SAPO-34 membrane was modeled, validated and used to investigate the effect of feed pressure, and composition on the selectivity of propylene over propane at 303 K. This model was further extended to simulate the performance of SAPO-34 tubular membrane for C3 separation for its practical utility. Based on the obtained results, SAPO-34 is found to be a potential candidate for kinetic separation of C3 mixtures at near ambient conditions. (C) 2010 Elsevier Inc. All rights reserved.