title: Quantitative analysis of nitrogen containing compounds in microalgae based bio-oils using comprehensive two-dimensional gas-chromatography coupled to nitrogen chemiluminescence detector and time of flight mass spectrometer.
abstract: Insight in the composition of the algae derived bio-oils is crucial for the development of efficient conversion processes and better upgrading strategies for microalgae. Comprehensive two-dimensional gas chromatography (GC×GC) coupled to nitrogen chemiluminescence detector (NCD) and time-of-flight mass spectrometer (TOF-MS) allows to obtain the detailed quantitative composition of the nitrogen containing compounds in the aqueous and the organic fraction of fast pyrolysis bio-oils from microalgae. Normal phase (apolar×mid-polar) and reverse phase column (polar×apolar) combination are investigated to optimize the separation of the detected nitrogen containing compounds. The reverse phase column combination gives the most detailed information in terms of the nitrogen containing compounds. The combined information from the GC×GC-TOF-MS (qualitative) and GC×GC-NCD (quantitative) with the use of a well-chosen internal standard, i.e. caprolactam, enables the identification and quantification of nitrogen containing compounds belonging to 13 different classes: amines, imidazoles, amides, imides, nitriles, pyrazines, pyridines, indoles, pyrazoles, pyrimidines, quinolines, pyrimidinediones and other nitrogen containing compounds which were not assigned to a specific class. The aqueous fraction mostly consists of amines (4.0wt%) and imidazoles (2.8wt%) corresponding to approximately 80wt% of the total identified nitrogen containing compounds. On the other hand, the organic fraction shows a more diverse distribution of nitrogen containing compounds with the majority of the compounds quantified as amides (3.0wt%), indoles (2.0wt%), amines (1.7wt%) and imides (1.3wt%) corresponding to approximately 65wt% of the total identified nitrogen containing compounds.
authors.affiliation: Ghent University, Laboratory for Chemical Technology, Technologiepark 914, 9052 Ghent, Belgium.
authors.forename: Hilal E
authors.initials: HE
authors.lastname: Toraman
authors.affiliation: Ghent University, Laboratory for Chemical Technology, Technologiepark 914, 9052 Ghent, Belgium.
authors.forename: Kristina
authors.initials: K
authors.lastname: Franz
authors.affiliation: Ghent University, Department of Biosystems Engineering, Coupure Links 653, 9000 Ghent, Belgium.
authors.forename: Frederik
authors.initials: F
authors.lastname: Ronsse
authors.affiliation: Ghent University, Laboratory for Chemical Technology, Technologiepark 914, 9052 Ghent, Belgium. Electronic address: Kevin.VanGeem@UGent.be.
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Van Geem
authors.affiliation: Ghent University, Laboratory for Chemical Technology, Technologiepark 914, 9052 Ghent, Belgium.
authors.forename: Guy B
authors.initials: GB
authors.lastname: Marin
mesh_terms: D000588:Amines / Q000032:analysis / Q000737:chemistry; D056148:Chromatography, Reverse-Phase; D008401:Gas Chromatography-Mass Spectrometry; D008163:Luminescent Measurements; D058086:Microalgae / Q000737:chemistry* / Q000378:metabolism; D017672:Nitrogen Compounds / Q000032:analysis* / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000588:Amines; D017672:Nitrogen Compounds; D010938:Plant Oils
keywords: Bio-oil; Fast pyrolysis; GC×GC–NCD/TOF-MS; Microalgae; Nitrogen containing compounds