Sonochemical Synthesis of UiO-66 for CO 2 Adsorption and Xylene Isomer Separation

Abstract

Zr-benzendicarboxylate structure, UiO-66 was prepared in 1-L batch scale by using a unique sonochemi- cal-solvothermal combined synthesis method. The produced UiO-66 showed uniform particles of ca. 0.2 µm in size with the BET surface area of 1,375 m2/g in high product yield (>95%). The UiO-66 showed 198 and 84 mg/g CO2 adsorption capacity at 273 K and 298 K, respectively, with excellent CO2 selectivity (CO2:N2=32:1) at ambient conditions. The isosteric heat of CO2 adsorption varied from 33 to 25 kJ/mol as the adsorption progressed. The UiO-66 tested for xylene isomer sep- aration in a liquid-phase batch mode confirmed preferential adsorption of the adsorbent for o-xylene over m-, and p-xylene.