Targeted functionalization of porous materials for separation of alcohol/water mixtures by modular assembly

Three isoreticular hydrogen-bonded frameworks with functionalized pore structures were constructed by a modular self-assembly process in which a series of amino acids with various substituents serve as facile exchange subassemblies to decorate the pore wall. The ordered amino acid side-chain groups in the pore channels play an important role in determining the adsorption behavior of the framework materials, and ensure exclusive adsorption of methanol/water over ethanol. Gas-chromatographic separation experiments demonstrated that alcohols can be efficiently separated from ternary water/methanol/ethanol mixtures and revealed a key influence of the adsorbate-host framework interaction on the practical separation performance of mixtures.