Figure 11.

Adsorption isotherms of xylene isomers as (a) single components (total loading mixture is the sum of the loadings of xylenes from the mixture at chemical equilibrium) and (b) a mixture at chemical equilibrium in MFI-type zeolites at 523 K. (c) Mole fractions of xylene isomers as a function of the total pressure for the mixture at chemical equilibrium adsorbed in the MFI-type zeolite and for the bulk phase. The composition in the bulk phase follows from Figure 1a. (d) Changes in enthalpy ΔH_tr,i and entropy TΔS_tr,i at 523 K due to the transfer of xylene i from the fluid-phase mixture at chemical equilibrium to the MFI-type zeolite at 0.3 and 30 bar. (e) Typical snapshot of the simulation of adsorption of the mixture of xylenes in the MFI-type zeolite at 300 bar and 523 K. m-Xylene is shown in blue, p-xylene in gray, and o-xylene in orange. The snapshot shows how xylenes are located in the intersection of the zigzag and straight channels of MFI-type zeolites.