A constant-volume constant-pressure system was used to measure the adsorption isotherms and diffusion coefficients of C6 (hexane, cyclohexane, benzene) and C8 (p-xylene, m-xylene, o-xylene, ethylbenzene) hydrocarbons in silicalite at 20 to 200C. The differences in the equilibrium adsorption capacity and diffusion coefficients for these hydrocarbons were explained in terms of the shape-selective characteristics of the silicalite and the size of the adsorbate molecules. The diffusivities of benzene, ethylbenzene, p-xylene, m-xylene and o-xylene at 293K were 8.6 x 10-12, 7.5 x 10-12, 9.9 x 10-12, 4.1 x 10-12 and 2.2 x 10-12cm2/s, respectively.

Adsorption and Diffusion of C6 and C8 Hydrocarbons in Silicalite. P.Wu, A.Debebe, Y.H.Ma: Zeolites, 1983, 3[2], 118-22