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Updated: Jul 12, 2026
10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
A Hydrocarbon Organic Cage-Based Porous Liquid for Ethylene/Ethane Separation.
Haochen Wang1, Peiren Liu1, Lukman O Alimi1
1Smart Hybrid Materials (SHMs) Laboratory, Physical Science and Engineering (PSE) Division, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Journal of the American Chemical Society
|July 10, 2026
Summary
We developed a novel porous liquid (PL) using hydrocarbon cages for selective gas separation. This fluid material efficiently separates ethylene from ethane, showcasing its potential for challenging hydrocarbon separations.
Area of Science:
- Materials Science
- Chemical Engineering
- Supramolecular Chemistry
Background:
- Porous liquids (PLs) offer unique fluidic porosity for gas separation.
- Existing PLs often rely on complex or non-hydrocarbon components.
- Tailoring PLs for specific separations remains a key challenge.
Purpose of the Study:
- To create a Type II porous liquid using purely hydrocarbon molecular cages.
- To demonstrate selective ethylene/ethane separation using the developed PL.
- To establish hydrocarbon cages as versatile building blocks for tunable PLs.
Main Methods:
- Synthesis of a shape-persistent, purely hydrocarbon molecular cage.
- Formation of a Type II PL by dissolving the cage in a size-excluded solvent.
- Characterization using structural analysis, molecular dynamics (MD) simulations, and positron annihilation lifetime spectroscopy (PALS).
- Evaluation of ethylene/ethane separation performance via adsorption-desorption cycles.
Main Results:
- Confirmed permanent porosity and effective solvent exclusion in the liquid state.
- Demonstrated selective uptake of ethylene over ethane by the PL.
- Achieved iterative enrichment to ~90% ethylene purity from an equimolar mixture.
- Showcased the hydrocarbon cage's strong CO2 physisorption affinity in the solid state.
Conclusions:
- Purely hydrocarbon organic cages are effective building blocks for Type II PLs.
- Rational design of cage size, shape, and solvent exclusion enables tailored separations.
- This PL technology offers a promising approach for challenging hydrocarbon separations.
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