Enhanced adsorption performance of gaseous toluene on defective UiO-66 metal organic framework: Equilibrium and kinetic studies.

Abstract

In this study, defective UiO-66 materials modified with Cetyltrimethylammonium bromide (CTAB) surfactant were successfully synthesized by a simple approach. Adsorption and desorption performance as well as the corresponding kinetics of toluene vapor for UiO-66 and the modified materials were intensively studied. The physical and chemical properties of the sample were obtained by a series of characterization techniques. As indicated by the experiments, the number of missing-linker defect sites in UiO-66 were influenced by the CTAB concentration. The presence of the defect sites was served as the main active adsorption sites for efficient toluene vapor adsorption. In result, adsorptive capacity of toluene over CTAB-U-0.5 was improved to 275\u2009mg\u2009g-1, which was much higher than that of UiO-66 (151\u2009mg\u2009g-1). The effects of adsorption temperature, initial toluene concentration and relative humidity on the adsorption capacity of 1000\u2009ppm toluene on UiO-66 were further explored. Furthermore, as-prepared CTAB-modified UiO-66 materials were used for reprocessing cycles, which showed excellent regeneration performance.