Characterizing Olefin Selectivity and Stability of Silver Salts in Ionic Liquids Using Inverse Gas Chromatography

Date
2020-11-23
Authors
Eor, Philip
Ryoo, Donghyun
Nan, He
Anderson, Jared
Journal Title
Journal ISSN
Volume Title
Publisher
Altmetrics
Authors
Research Projects
Organizational Units
Ames Laboratory
Organizational Unit
Chemistry
Organizational Unit
Journal Issue
Series
Abstract

Separation systems utilizing silver(I) ion-olefin complexation have limitations since silver(I) ions can be poisoned or reduced to metallic silver. Ionic liquids (ILs) are used as solvents for silver(I) ions to facilitate separations since their physico-chemical properties can be easily tuned. To develop separation systems with sustainable olefin selectivity, factors that affect silver(I) ion stability need to be understood. In this study, a total of 13 silver salt/IL mixtures were examined by inverse gas chromatography to identify the effects of silver salt anion and IL cation/anion combination on silver(I) ion stability. The effects of temperature and three different exposure gases on silver(I) ion stability were systematically studied. Exposing silver salt/IL mixtures to hydrogen at high temperatures had a greater effect on decreasing silver(I) ion-olefin complexation. Silver(I) ions from the silver bis[(trifluoromethyl)sulfonyl]imide ([NTf2–]) salt were more stable in [NTf2–]-containing ILs than in [BF4–]-containing ILs. Optimum mixtures exhibited high olefin selectivity and were stable beyond 90 h when exposed to hydrogen gas.

Description
Keywords
Citation
Collections