Petrochemical analysis - Getting more from Gas Chromatography

Chemical fingerprinting of crude oils: Gaining an extra dimension from GCxGC -TOF MS

The enhanced separation offered by comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOF MS) has made the technique a popular choice for petrochemical analyses.

Intelligent GC Solutions based on Capillary Flow Technology

The complexity of petrochemical fractions have challenged analytical scientists to this present day. In hydrocarbon processing, dedicated analyzers are commonly used and are often based on multidimensional approaches, allowing column switching, isolation of fractions and/or column back-flushing. These analyzers are well suited for a given application but lack flexibility. Moreover, since gas valves are used to direct fractions to different columns or detectors, these valves have limitations in operating temperature, resulting in sample discrimination (of higher boiling fractions), and are also prone to adsorption of more polar or reactive solutes since they are placed inside the sample pathway. 

Using Nitrogen instead of Helium as carrier gas, while maintaining exact the same separation efficiency, retention times, peak elution order, without changing the oven temperature conditions.

For several reasons, there is interest to replace helium for a different carrier gas in gas chromatography. Hydrogen is the obvious choice, but there is a concern on safety and reactivity. It is also possible to use nitrogen, but this is often not considered because it has a low optimal flow and velocity.