Functionalization of metal organic frameworks by [BMIM][CH₃COO] ionic liquid for toluene capture

Indoor exposure to volatile organic compounds (VOCs) is detrimental to the health of the occupants, and their removal is crucial in maintaining good air quality. Novel adsorbents prepared by modifying Metal-Organic Frameworks (MOFs), MIL101 (Cr), UiO-66, and UiO-66-NH₂ with [BMIM][CH₃COO] ionic liquid, were characterized and tested for toluene adsorption. [BMIM][CH₃COO]/MIL101 performed best with a fast sorption rate, large sorption capacity, and good regenerability. It displays synergistic interactions between the IL and MOF. Adding one weight percent [BMIM][CH₃COO] to UiO-66 and UiO-66-NH₂ has a synergistic effect with respective 14% and 5% enhancements sorption over calculated values. The strong interactions between IL and UiO-66 and UiO-66-NH₂, as observed in their thermogravimetric data, results in poor toluene sorption for 10 wt% [BMIM][CH₃COO] loadings. This work provides a basis for IL modification of MOFs for enhanced sorption of VOCs for air treatment.