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Updated: Feb 6, 2026

Sulfate Separation by Selective Crystallization with a Bis-iminoguanidinium Ligand
Published on: September 8, 2016
Separation of Aromatics/Cyclic Aliphatics by Nonporous Adaptive Pillararene Crystals
Kecheng Jie1, Yujuan Zhou1, Errui Li1
1State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University, Hangzhou, 310027, P. R. China.
Abstract:
The separation of cyclic aliphatics of high purity, which are produced from hydrogenation of the corresponding aromatics, is highly desired in the chemical industry. An energy-efficient and environmentally friendly adsorptive separation method using nonporous adaptive crystals of perethylated pillar[5]arene (EtP5) and pillar[6]arene (EtP6) is described. Adaptive EtP5 crystals separate toluene from methylcyclohexane with 98.8 % purity, while adaptive EtP6 crystals separate methylcyclohexane from toluene with 99.2 % purity. The selectivities come from the stability of new EtP5 and EtP6 crystal structures upon capture of toluene and methylcyclohexane, respectively. The reversible transformations between nonporous guest-free EtP5 or EtP6 structures and guest-loaded structures make them highly recyclable.
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