Transient diffusion, sorption, and desorption of cyclopropane in NaX zeolite

Abstract

Transient diffusion, sorption, and desorption experiments of cyclopropane in Nax zeolite at 1 bar in a flow microreactor reveal that the nature of the diluent gas used in the sorbate mixture affects the kinetics of intracrystalline mass transport of cyclopropane in the zeolite. The rate of intracrystalline mass transport and the equilibrium uptake are strongly dependent on temperature. The outward mass transport of cyclopropane into 1 bar Ar gas is found to be an activated process with an apparent activation energy of 7.4 kcal/mol. Rates of diffusion are affected by the gas phase pressure. The enthalpy of sorption for cyclopropane at loadings approaching zero is found to be -9.0 kcal/mol, and the entropy of sorption is -18.2 cal/mol-K. © 1991.