Computational design of metal-organic frameworks for aniline recovery from aqueous solution

In this work, molecular simulations combined with experimental measurements were conducted to screen candidate metal-organic frameworks (MOFs) for aniline recovery from aqueous solution. The structure-property relationships that can correlate the recovery performance of the MOFs to their physicochemical features were analyzed. The results show that the interplay between the isosteric heat of adsorption of aniline and the free volume of the material is crucial to the aniline recovery capability of MOFs at low concentrations. In contrast, the aniline uptake at high concentrations is dominated by the material's free volume as usually expected. In addition, the requirements of the best MOF candidates for aniline recovery were suggested in this study. Based on the conclusions drawn from the screening route, several novel MOFs were further computationally designed, which possess high aniline uptake within the whole range of concentrations examined. The obtained information may be helpful for in-depth research to broaden the applications of MOFs in mixture separation under liquid phase conditions.