Development of two‐dimensional gas chromatography (GC×GC) coupled with Orbitrap‐technology‐based mass spectrometry: Interest in the identification of biofuel composition

Abstract

Comprehensive gas chromatography (GC) has emerged in recent years as the technique of choice for the analysis of volatile and semivolatile compounds in complex matrices. Coupling it with high‐resolution mass spectrometry (MS) makes a powerful tool for identification and quantification of organic compounds. The results obtained in this study showed a significant improvement by using GC×GC‐EI‐MS in comparison with GC‐EI‐MS; the separation of chromatogram peaks was highly improved, which facilitated detection and identification. However, the limitation of Orbitrap mass analyzer compared with time‐of‐flight analyzer is the data acquisition rate; the frequency average was about 25 Hz at a mass resolving power of 15.000, which is barely sufficient for the proper reconstruction of the narrowest chromatographic peaks. On the other hand, the different spectra obtained in this study showed an average mass accuracy of about 1 ppm. Within this average mass accuracy, some reasonable elemental compositions can be proposed and combined with characteristic fragment ions, and the molecules can be identified with precision. At a mass resolving power of 7.500, the scan rate reaches 43 Hz and the GC×GC‐MS peaks can be represented by more than 10 data points, which should be sufficient for quantification. The GC×GC‐MS was also applied to analyze a cellulose bio‐oil sample. Following this, a highly resolved chromatogram was obtained, allowing EI mass spectra containing molecular and fragment ions of many distinct molecules present in the sample to be identified.

Review on Evolved Gas Analysis Mass Spectrometry with Soft Photoionization for the Chemical Description of Petroleum, Petroleum-Derived Materials, and Alternative Feedstocks

“…Hung et al recently presented GC × GC with Orbitrap-based high-resolution mass spectrometry for the chemical description of bio-oils. Despite using hard electron ionization nicely allowing for a spectral database search in the National Institute of Standards and Technology (NIST) library, the authors conclude that a soft ionization could provide tremendous support . Recently, the group of Qi and co-workers stronger moved into the field of bio-oil research by studying the hydrodeoxygenation of model compounds over a nitrogen-doped carbon-supported palladium catalyst.…”

“…Despite using hard electron ionization nicely allowing for a spectral database search in the National Institute of Standards and Technology (NIST) library, the authors conclude that a soft ionization could provide tremendous support. 154 Recently, the group of Qi and co-workers stronger moved into the field of bio-oil research by studying the hydrodeoxygenation of model compounds over a nitrogen-doped carbon-supported palladium catalyst. The group reports an efficient deoxygenation of lignin model compounds at the same time, preserving the aromaticity, stating "extremely advantageous for the concept of selective conversion of lignin into value-added aromatic chemicals".…”

Two-Dimensional Gas Chromatography Characterization of Pyrolysis Bio-oils: A Review

“… a Links to references: , , , , , , , , , , , , , , , , , , , , , − , − , , , − , , , , , , , , , , , , , , , , , , , , , and . …”

“…At a mass resolving power of 7500, the scanning rate was 43 Hz, and the resulting GC × GC peaks were represented by more than ten data points, which was sufficient for the quantification. On the other hand, high mass resolution combined with a great mass accuracy of about 1 ppm allowed one to generate the elemental compositions from the measured mass, which improved the identification …”

Advanced mono‐ and multi‐dimensional gas chromatography–mass spectrometry techniques for oxygen‐containing compound characterization in biomass and biofuel samples

“…At a mass RP of 15.000, the frequency average is about 25 Hz, which may not be enough for a proper reconstruction of the narrowest chromatographic peaks. Another limitation is the need to use Orbitrap libraries for the identification since the NIST libraries can lead to some misannotations [94].…”