O'Hearn Daniel J, Sensharma Debobroto, Raza Asif, Bezrukov Andrey A, Vandichel Matthias, Mukherjee Soumya, Zaworotko Michael J
Department of Chemical Sciences, Bernal Institute, University of Limerick Limerick V94 T9PX Ireland
SSPC, Science Foundation Ireland Research Centre for Pharmaceuticals, University of Limerick Limerick V94 T9PX Ireland.
Chem Sci. 2024 Sep 27;15(43):17937-43. doi: 10.1039/d4sc03029j.
Hybrid ultramicroporous materials (HUMs) comprised of combinations of organic and inorganic linker ligands are a leading class of physisorbents for trace separations involving C1, C2 and C3 gases. First generation HUMs are modular in nature since they can be self-assembled from transition metal cations, ditopic linkers and inorganic "pillars", as exemplified by the prototypal variant, SIFSIX-3-Zn (3 = pyrazine, SIFSIX = SiF ). Conversely, HUMs that utilise chelating ligands such as ethylenediamine derivatives are yet to be explored as sorbents. Herein, we report the structures and sorption properties of two HUMs based upon the chelating ligand , -bis(pyridin-4-ylmethyl)ethane-1,2-diamine (enmepy), [Zn(enmepy)(SiF)] (SIFSIX-24-Zn) and [Zn(enmepy)(SO)] (SOFOUR-2-Zn). These HUMs are isostructural and exhibit high CH uptakes of 85 cm g (3.79 mmol g) and 79 cm g (3.52 mmol g), and CH/CO IAST selectivities of 7.4 and 8.1 (1 bar, 1 : 1 mixture, 298 K), respectively. Dynamic column breakthrough experiments resulted in separation factors of 5.26 and 2.05, and CO effluent purities of 99.991 and 99.989%, respectively. Temperature programmed desorption experiments at 60 °C resulted in rapid desorption of CO, followed by fuel grade CH (>98%), affording productivities of 9.45 and 7.96 L kg and maximum CH outlet purities of 99.92% and 99.66%, respectively. This study introduces the use of diamine chelating ligands in HUMs for gas separations through two parent sorbents that are prototypal for families of related materials, one of which, SOFOUR-2-Zn, uses the earth-friendly sulfate anion as a pillar.
由有机和无机连接配体组合而成的混合超微孔材料（HUMs）是用于涉及C1、C2和C3气体的痕量分离的一类主要物理吸附剂。第一代HUMs本质上是模块化的，因为它们可以由过渡金属阳离子、双齿连接体和无机“支柱”自组装而成，典型的变体SIFSIX-3-Zn（3 = 吡嗪，SIFSIX = SiF ）就是例证。相反，利用螯合配体（如乙二胺衍生物）的HUMs作为吸附剂尚未得到探索。在此，我们报告了基于螯合配体1,2-双（吡啶-4-基甲基）乙烷-1,2-二胺（enmepy）的两种HUMs的结构和吸附性能，即[Zn(enmepy)(SiF)] （SIFSIX-24-Zn）和[Zn(enmepy)(SO)] （SOFOUR-2-Zn）。这些HUMs具有相同的结构，对CH的高吸附量分别为85 cm³ g⁻¹（3.79 mmol g⁻¹）和79 cm³ g⁻¹（3.52 mmol g⁻¹），以及CH₄/CO₂的IAST选择性分别为7.4和8.1（1 bar，1∶1混合物，298 K）。动态柱穿透实验得到的分离因子分别为5.26和2.05，CO₂流出物纯度分别为99.991%和99.989%。在60℃下的程序升温脱附实验导致CO₂快速脱附，随后是燃料级CH₄（>98%），生产率分别为9.45和7.96 L kg⁻¹，CH₄出口最大纯度分别为99.92%和99.66%。本研究通过两种母体吸附剂介绍了二胺螯合配体在HUMs用于气体分离中的应用，这两种母体吸附剂是相关材料家族的原型，其中一种，即SOFOUR-2-Zn，使用对环境友好的硫酸根阴离子作为支柱。
