Industrial & Engineering Chemistry Research, Vol.59, No.30, 13744-13754, 2020
High n-Hexane Adsorption Capacity of Composite Adsorbents Based on MOFs and Graphene with Various Morphologies
Adsorption is an important technique for the separation and purification of various gases. In this study, two types of graphene materials with various morphologies are employed to modify metal-organic frameworks (MOFs) and improve their adsorption capacities. SEM, XRD, as well as Raman and IR spectroscopies are adopted to analyze the microstructures of these as-prepared samples. After the combination process, the adsorption abilities of UiO-66 and ZIF-8 are enhanced significantly (an increase of more than 48% for the n-hexane adsorption), and the adsorption amounts of CO2, methanol, and n-hexane reach 9.32, 17.48, and 4.26 mmol g(-1), respectively. The remarkably improved performances are induced by the more favorable orbit interaction between the graphene basal plane and the adsorbed gases. Moreover, the natural three-dimensional (3D) continuous and porous structure of the 3D graphene network is not only beneficial to the adsorption ability but also improves the stability of MOFs at a high temperature.