Adsorptive Separation of Benzene, Cyclohexene, and Cyclohexane by Amorphous Nonporous Amide Naphthotube Solids

Benzene hydrogenation is an important industrial process. The reaction is incomplete, resulting in a mixture of benzene, cyclohexane, and/or cyclohexene that have to be separated before any further reactions. The currently used extractive and azeotropic distillations are operationally complex and energy intensive. Adsorptive separation provides an alternative energy‐efficient method. However, the separation of the ternary mixture by adsorptive separation has not yet been reported. In the present research, we report two macrocyclic hosts with hydrogen‐bonding sites in their cavities that are able to separate the ternary mixture of benzene, cyclohexene, and cyclohexane. N−H⋅⋅⋅π interactions were found to play a key role in the selective separation. In addition, fast adsorption, high loading ratios, and easy recycling are achieved with the present system, which is promising for practical applications. Mixtures of benzene, cyclohexene, and cyclohexane can be separated through solid‐vapor adsorption by using the activated solids of amide naphthotubes. N−H⋅⋅⋅π interactions are found to play a key role in the adsorption selectivity among the three structurally similar molecules.