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Abstract Propylene is a crucial building block to produce many industrial‐scale chemicals including polypropylene. The separation of propylene from propane to reach the high‐purity levels needed for downstream applications is a difficult task due to the close similarities in their physical properties. The olefin/paraffin separation including that involving propylene mainly relies on highly energy‐intensive distillation processes and accounts for nearly 0.3% of the global energy consumption. The utility of a copper complex supported by a fluorinated bis(pyrazolyl)borate is demonstrated to accomplish the separation of propylene from propane repeatedly, under mild conditions with high selectivity. Complete characterization of a rare, copper(I) propylene complex is also reported including the molecular structure.
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Ionic Liquid Stabilizes Olefin Facilitated Transport Membranes Against Reduction
Abstract Separation of olefins from their paraffin analogs relies on energy‐intensive cryogenic distillation. Facilitated transport‐based membranes that reversibly and selectively bind olefins, but not paraffins, could save considerable amounts of energy. However, the chemical instability of the silver ion olefin‐binding carriers in such membranes has been a longstanding roadblock for this approach. We discovered long‐term carrier stability against extended exposure to hydrogen, a common contaminant in such streams. Based on UV/Vis absorption and Raman spectroscopy, along with XRD analysis results, certain ionic liquids solubilize silver ions, and anion aggregates surrounding the silver ion carriers greatly attenuate their reduction by hydrogen. Here, we report the stability of olefin/paraffin separation properties under continuous exposure to high pressure hydrogen, which addresses a critical technical roadblock in membrane‐based olefin/paraffin separation.
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- Award ID(s):
- 1647722
- PAR ID:
- 10446950
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 134
- Issue:
- 25
- ISSN:
- 0044-8249
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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