Pyrolysis of Residual Tobacco Seeds: Characterization of Nitrogen Compounds in Bio-oil Using Comprehensive Two-Dimensional Gas Chromatography with Mass Spectrometry Detection

Abstract

Energetic tobacco (EnT) is a type of genetically modified tobacco with a focus on energy. Its seeds are larger and appear in greater quantity than those of conventional tobacco. This plant easily adapts to unproductive soils and is practically free of nicotine. The oil seed from EnT can be used for producing biodiesel without competition with edible oils. Additionally, the resulting residual cake can be thermally degraded to bio-oil and biochar through pyrolysis processes. In this study, the fast pyrolysis (700 °C at 100 °C min–1) of the residual cake of EnT seeds was performed in a fixed bed reactor (quartz), yielding approximately 40% (in mass) liquid products (bio-oil and an aqueous phase). After removal of the aqueous phase, the organic phase was submitted to an acid–alkaline extraction of the N-compounds in a simple and efficient way. The bio-oil and alkaline extract were analyzed by comprehensive two-dimensional gas chromatography coupled to fast-quadrupole mass spectrometry. Compounds were tentatively identified by similarity with a commercial library of mass spectra and using retention indexes. The main classes of compounds identified were phenols, hydrocarbons, and N-compounds (imidazole, pyridine, and their derivatives), with the potential to be applied in the chemical and pharmaceutical industries as well as biofuel production. The alkaline extraction resulted in the isolation of the main N-components, a finding fundamental for the utilization of these compounds for the production of pharmaceuticals, pesticides, and polymers.

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

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Liquid fuel from waste tires: novel refining, advanced characterization and utilization in engines with ethyl levulinate as an additive

“…The exciting principle behind twodimensional GC Â GC TOFMS is the separation of mixtures by the polarity of species compared to one-dimensional GC-MS separation based on the compounds' boiling point. [28][29][30]36 There are very few studies in the literature regarding the analysis of tire oil fractions using this advanced chromatographic technique. Ngxangxa reported that TPO is a complex mixture of C 6 -C 24 compounds, including paraffins, terpenes, monocyclic and PAHs, heterocyclic compounds, etc.…”

Production and characterization of bio-oils from fast pyrolysis of tobacco processing wastes in an ablative reactor under vacuum

“…One dimensional GC has been used for many years; however, there remain minor shortcomings in obtaining the best compound separation using this technique. Increasing the resolution and detectability of liquid oil could be obtained using higher-dimensional GC techniques [27], allowing for the detection of a higher number of compounds. A 2-dimensional, GCxGC/TOF MS analysis is believed to be more efficient in identifying more organic compounds in the organic fraction than traditional GC-MS.…”