Presentation Profile
Orthogonal Selectivity for Separation of oxygenated compounds and hydrocarbons in alternative fuels by 2D GC using Zebron® ZB-1701™ and ZB-1™ GC Columns
Currently Scheduled: 10/15/2019 - 3:35 PM - 3:55 PM
Room: South Lobby
Main Author
Ramkumar Dhandapani - Phenomenex
- Timothy Nelson - Phenomenex
- Badaoui Omasi - Phenomenex
Abstract:
The need to diversify energy sources in the transportation field has sparked great interest in direct coal liquefaction products. Before processing, these liquids properties and compositions are far from fuel specifications and upgrading must be applied to the gas oil cuts. In fact, they consist mainly of aromatic hydrocarbons, cyclic alkanes (naphthenes), and heteroatomic compounds, especially oxygenated species. To consider their co-refining with petroleum cuts, it is crucial to study their chemical and physical properties. Apart from the hydrocarbons, the requirements in terms of molecular characterization improvement concern oxygenated compounds which belong to many different chemical families and are present in relatively high concentrations before hydrodeoxygenation (HDO). Multidimensional Gas Chromatography has never been at stake to surmount this challenge. Yet, this powerful tool allows the analysis of complex samples and offers a high peak capacity by combining two different stationary phases with different separation mechanisms. Results obtained using GC×GC-FID enabled to unravel molecular structures of oxygenated compounds in a coal-derived middle distillate. It shows that oxygenated structures mainly consist in phenolic compounds. Compared to conventional configurations, a reversed configuration involving a highly polar column in the first dimension and a non-polar one in the second enables the separation of oxygenates but also hydrocarbons in one single run. In fact, 2D contour plots obtained in these conditions exhibit good resolution and high space occupation. Nevertheless, nitrogenates elute in the same zone as oxygenates and a proper quantification is therefore hardly reachable. Limitations of GC×GC can also be overcome by using a multi-technical analytical approach involving sample preparation or fractionation.
