Ryoo Donghyun, Bara Jason E, Anderson Jared L
Department of Chemistry, Iowa State University, Ames, IA 50011, USA; Ames National Laboratory-U.S. Department of Energy, Ames, IA, 50011, USA.
Department of Chemical and Biological Engineering, University of Alabama, Tuscaloosa, AL, 35487, USA.
J Chromatogr A. 2025 Aug 30;1757:466137. doi: 10.1016/j.chroma.2025.466137. Epub 2025 Jun 10.
The development of efficient and selective olefin separation technologies is a critical challenge within the chemical industry given the high energy demands of conventional cryogenic distillation methods. To address this, the study explores the effectiveness of polymeric ionic liquid (PIL) stationary phases in gas chromatography (GC) that incorporate both silver(I) ([Ag]) and copper(II) ([Cu]) ions for enhanced olefin separation via π-complexation interactions. The effects of both non-crosslinked and crosslinked PIL stationary phases containing varying ratios of [Ag⁺] and [Cu²⁺] ions were systematically investigated to evaluate their impact on the separation of olefins from paraffins and structurally similar olefins. Retention measurements using a broad range of olefinic probes revealed that [Ag⁺] ions provided stronger and more consistent π-complexation in PIL-based stationary phases, while [Cu²⁺] ions preferentially enhance olefin retention in crosslinked systems. Furthermore, thermal stability studies showed that [Ag]-containing PIL stationary phases maintain stable olefin separation efficiency over prolonged exposure under elevated temperatures, while crosslinked PIL stationary phases containing [Cu] ions exhibited stronger retention due to increased surface adsorption. These findings provide insight into the tunability of metal-olefin interactions using PIL-based stationary phases and suggest design strategies for achieving thermally stable and highly selective chromatographic separations of unsaturated hydrocarbons.
鉴于传统低温蒸馏方法对能源的高需求，开发高效且选择性的烯烃分离技术是化学工业面临的一项关键挑战。为解决这一问题，该研究探索了气相色谱法（GC）中聚合物离子液体（PIL）固定相的有效性，这些固定相含有银（I）（[Ag]）和铜（II）（[Cu]）离子，以通过π络合相互作用增强烯烃分离效果。系统研究了含有不同比例[Ag⁺]和[Cu²⁺]离子的非交联和交联PIL固定相的影响，以评估它们对从石蜡和结构相似的烯烃中分离烯烃的影响。使用多种烯烃探针进行的保留测量表明，[Ag⁺]离子在基于PIL的固定相中提供了更强且更一致的π络合，而[Cu²⁺]离子优先增强交联体系中烯烃的保留。此外，热稳定性研究表明，含[Ag]的PIL固定相在高温下长时间暴露后仍能保持稳定的烯烃分离效率，而含[Cu]离子的交联PIL固定相由于表面吸附增加而表现出更强的保留。这些发现为使用基于PIL的固定相调节金属 - 烯烃相互作用提供了见解，并提出了实现不饱和烃热稳定和高选择性色谱分离的设计策略。
