Kinetic separation of alkylbenzenes with metal-organic framework compounds

Abstract

Metal-organic framework (MOF) compounds consisting of terephthalic acid and cations (Cr3+, In3+ Al3+ Cu2+and Zn2+ were prepared by the hydro- and solvo-thermal methods and characterized by XRD, N2 adsorptiondesorption isotherm, TG-DTA and FE-SEM. The prepared MOFs were crystalline and phase-pure. MOFs were used as column packings for chromatographic separation of alkylbenzenes. MOFs recognized differences in molecular sizes in addition to boiling points of alkylbenzenes. Activation energy for diffusion in the MOF micropores ranged from 25 to 60 kJ mol-1. Temperature-programmed XRD measurement in air revealed that no expansion or contraction of MOF frameworks occurred up to 230°C.