|Abstract Title:||Unique Selectivity & Capabilities of Ionic Liquid GC Capillary Columns including Measurement of Water by GC|
|Presenter Name:||Mr Klaus Buckendahl|
|Co-authors:||Dr Leonard Sidisky|
Mr James Decorcie
Mr Greg Baney
Mr Michael Buchanan
|Company/Organisation:||Merck / Sigma-Aldrich Chemie GmbH|
|Session Choice:||Analytical Techniques: Chromatography and Separations|
Abstract Information :
Choosing a stationary phase is the most critical step in column selection, more important than the column's I.D., film thickness, or length. This is because the stationary phase determines the selectivity of the column, and that selectivity influences resolution. Changing stationary phase may be an effective way to increase resolution.
Beginning in 2006, extensive evaluations of columns manufactured with ionic liquid stationary phases have occurred. Their main strength was discovered to be unique selectivity. These columns have the ability to perform many of the same applications as columns made with polysiloxane polymer or polyethylene glycol stationary phases of similar polarity, but with slight elution order changes, or even separations not possible on the traditional GC phases. Many times this results in increased resolution and/or shorter run times at the same time (e.g. separation/serial elution of hydrocarbon and FAME fraction in biodiesel).
Recent developments in column and ionic liquid phase technology lead to combine the unique selectivities of the most commonly used/ selective ionic liquid phases with improved inertness towards polar or active probes such as alcohols. This presentation will demonstrate the achieved improvements and expand also on recently introduced phases e.g. for the determination of benzene & oxygenates in reformulated gasoline or polyaromatic hydrocarbons (PAH), allowing baseline resolution of 22 PAH compounds (including the benzofluoranthrenes or dibenz[a,h]anthracene and indeno[1,2,3-cd]pyrene).
Furthermore the newest type of ionic liquid phases is introduced, suitable for quantitative water determination / direct injection of aqueous samples by / onto a GC Instrument. Previous work by Prof. Daniel Armstrong and co-workers has described the use of ionic liquid GC capillary columns for the trace analysis of the water content in a wide variety of solvents.  These columns provide a sharp water peak and enable a rapid and quantitative determination of water contents using very small sample amounts. This presentation further describes the characteristics and applicability of ionic liquid capillary columns for the GC analysis of water.