Park Sejoon, Morales-Collazo Oscar, Freeman Benny, Brennecke Joan F
McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
Angew Chem Int Ed Engl. 2022 Jun 20;61(25):e202202895. doi: 10.1002/anie.202202895. Epub 2022 Apr 21.
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.
从链烷烃类似物中分离烯烃依赖于能源密集型的低温蒸馏。基于促进传递的膜能够可逆且选择性地结合烯烃而非链烷烃，这可以节省大量能源。然而，此类膜中银离子烯烃结合载体的化学不稳定性长期以来一直是该方法的障碍。我们发现，在长期暴露于氢气（此类物流中的常见污染物）的情况下，载体具有稳定性。基于紫外/可见吸收光谱和拉曼光谱以及X射线衍射分析结果，某些离子液体可溶解银离子，并且银离子载体周围的阴离子聚集体极大地减弱了氢气对它们的还原作用。在此，我们报告了在持续暴露于高压氢气的情况下烯烃/链烷烃分离性能的稳定性，这解决了基于膜的烯烃/链烷烃分离中的一个关键技术障碍。
