Robust Microporous Metal–Organic Frameworks for Highly Efficient and Simultaneous Removal of Propyne and Propadiene from Propylene

Abstract

Simultaneous removal of trace amounts of propyne and propadiene from propylene is an important but challenging industrial process.W ereport herein aclass of microporous metal-organic frameworks (NKMOF-1-M)w ith exceptional water stability and remarkably high uptakes for both propyne and propadiene at lowp ressures. NKMOF-1-M separated at ernary propyne/propadiene/propylene (0.5 :0.5 :99.0) mixture with the highest reported selectivity for the production of polymer-grade propylene (99.996 %) at ambient temperature, as attributed to its strong binding affinity for propyne and propadiene over propylene.Moreover,wewere able to visualizep ropyne and propadiene molecules in the single-crystal structure of NKMOF-1-M through ac onvenient approach under ambient conditions,w hich helped to precisely understand the binding sites and affinity for propyne and propadiene.T hese results provide important guidance on using ultramicroporous MOFs as physisorbent materials.

Halogen–C2H2 Binding in Ultramicroporous Metal–Organic Frameworks (MOFs) for Benchmark C2H2/CO2 Separation Selectivity

“…The energetic „sweet spot“ for C 2 H 2 capture under ambient conditions is controlled by sorbent–C 2 H 2 binding interactions, which result from pore size and pore chemistry. This is exemplified by the current benchmark sorbents for CO 2 /N 2 , CO 2 /CH 4 , C 2 H 2 /C 2 H 4 , C 2 H 4 /C 2 H 6 , C 2 H 6 /C 2 H 4, propadiene/propylene, propyne/propylene, ternary propyne/propadiene/propylene, and C 4 olefins . Interestingly, the leading sorbents are ultramicroporous with tight binding sites, in which sorbate binding is driven by pore chemistry: strong electrostatics, H‐bonding sites, or open metal sites .…”

Separation of propyne, propadiene and propylene with carboxylate ionic liquids

“…丙烯是工业产量仅次于乙烯的重要烯烃原料， 主 要用作聚合单体生产如聚丙烯等下游产品， 被广泛用 于塑料、制药、纺织品、涂料等国民经济各个行业 [1][2][3][4] 。目前，丙烯生产主要通过蒸汽裂解的方式进行， 该技术会难以避免地引入少量丙炔和丙二烯等杂质 气体，严重影响后续的丙烯聚合过程，因此，实现丙 烯与丙炔和丙二烯有效分离是丙烯纯化过程中的关 键 [5,6] 。现有的丙炔/丙烯、丙二烯/丙烯分离技术主要 是选择性催化加氢， 通过将丙烯中的丙炔或丙二烯转 化为丙烯，从而达到丙烯纯化的效果，但该过程存在 丙烯过度加氢得到副产物丙烷的问题， 同时存在分离 能耗大、成本高等缺点，因此需要开发更为经济有效 的分离方法 [7,8] 。 近年来， 以离子液体作为溶剂的吸收分离技术受 到广泛关注 [9][10] 。 吸收分离技术流程简单， 处理量大， 同时离子液体具有极低的蒸气压、 良好的化学稳定性 和丰富的结构可设计性， 可以克服常规溶剂的局限性， 使吸收过程无溶剂损失，同时易于回收利用，无交叉 污染 [11][12] 。在气体分离领域，离子液体已被研究应用 于 CO2 捕集 [13][14][15][16] 、NH3 捕集 [17] 、H2S 和 SO2 脱除 [18][19][20] 以及低碳烃分离等方面 [21][22][23][24] 。其中，Kim 等人测定了 C2-C3 炔烃烯烃在几种咪唑类离子液体中的溶解度 [25] ， 其中 [ [26][27] ，有望与 丙炔和丙二烯分子发生相对较强的氢键相互作用， 获 得较高的溶解度 [28] ， 同时引入结构不对称的三丁基乙 基鏻阳离子([P4442] + )能显著降低离子液体粘度，且 合成的离子液体具备良好的热稳定性，分解温度在 580 K 左右 [29][30] [27][28] 进行溶解度测试前， 合成的离子液体经过 1 mbar [29][30]…”

Crystal engineering of porous coordination networks for C3 hydrocarbon separation

“…Chronology of key developments with respect to the use of PCNs for C3 hydrocarbon separation (reprinted with permission from Refs. 4,71,78,87–97. Copyright 2009, American Chemical Society; Copyright 2009, Elsevier B.V.; Copyright 2010, American Chemical Society; Copyright 2012, American Association for the Advancement of Science; Copyright 2016, American Association for the Advancement of Science; Copyright 2016, American Chemical Society; Copyright 2017, Elsevier B.V.; Copyright 2018, Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim; Copyright 2018, Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim; Copyright 2018, Elsevier B.V.; Copyright 2019, The Royal Society of Chemistry; copyright 2019, Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim; Copyright 2020, American Chemical Society; Copyright 2020, American Chemical Society).…”

“…At the time, ZU‐62 displayed a new record for C 3 H 4 (PD) uptake (1.74 mmol/g), high C 3 H 4 uptake (1.87 mmol/g), and very low uptake, 0.05 mmol/g, for C 3 H 6 at 5000 ppm and 298 K. This was attributed to the presence of a C 3 H 4 ‐selective Site III and a C 3 H 4 (PD)‐selective Site I. Breakthrough tests for C 3 H 4 /C 3 H 4 (PD)/C 3 H 6 (0.5:0.5:99) mixtures afforded an ultra‐pure stream of C 3 H 6 (over 99.9999%) through a one‐step purification process. Subsequently, Peng et al 4 reported two ultra‐microporous PCNs, NKMOF‐1‐M (M = Cu, Ni), which exhibited benchmark selectivity for ternary C 3 H 4 /C 3 H 4 (PD)/C 3 H 6 (0.5:0.5:99) mixtures. Recently, a Ca‐based MOF studied by Li et al 97 was also reported to simultaneously remove C 3 H 4 and C 3 H 4 (PD) from a ternary mixture of C 3 H 4 /C 3 H 4 (PD)/C 3 H 6 .…”