Enhanced VOCs adsorption with UIO-66–porous carbon nanohybrid from mesquite grain: A combined experimental and computational study

Abstract

In this study, adsorption of volatile organic compounds (VOCs) (here just gasoline vapor) by activated carbon- modified UIO-66 was investigated. First, activated carbon prepared from mesquite grain (ACPMG) and then UIO/ACPMG nanohybrid was synthesized by the solvothermal method. In following, the effect of main key parameters which effect on the surface and adsorption capacity such as the ratio of ACPMG to UIO-66 was studied. Physiochemical changes of as- synthesized samples were investigated by TGA, HR-TEM, PSD, SEM, EDX/MAP, BET, FT-IR, XRD, and XPS. It was found the UIO/ACPMG20% nanohybrid had the highest adsorption capacity (391.304 mg/g) for VOCs compared with the other samples, while the adsorption capacity of UIO-66, UIO/ACPMG10% nanohybrid, and UIO/ACPMG30% nanohybrid was 298.871, 309.523, and 320 mg/g respectively. UIO/ACPMG20% nanohybrid desorbed 285.71 mg/g of the adsorbed gasoline, which is an excellent result in desorption. So, the sample of UIO/ACPMG20% nanohybrid was selected as the optimum nano-adsorbent. In other hand, all the nano-adsorbent showed a rapid kinetic behavior for gasoline vapor adsorption and the maximum time for reaching a high adsorption capacity approximately was obtained in 20 min. Density functional theory calculations also performed to understand the adsorption characteristics of gasoline vapor on activated carbon-modified UIO-66.