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In this study, a material with great adsorption potential was obtained from the residual cake from the extraction of energetic tobacco seeds. This residual cake seed was characterized and subjected to pyrolysis in nitrogen flow, resulting in bio-oil and biochar. The biochar and the feedstock (waste cake of tobacco seeds) were characterized by several techniques (thermogravimetric analysis (TGA), elemental analysis infrared spectroscopy, scanning electron microscopy, inductively coupled plasma optical emission spectrometry(ICP-OES), the Brunauer Emmet Teller (BET) method, the Barret, Joyner, and Halenda (BJH) method and functional density theory (DFT)) for comparison and subsequent possible application of the biochar. The results of the ICP-OES analyses indicate that nitrogen, potassium and phosphorus are the most abundant elements in the biomass and biochar. The metals analysis indicated no toxicological effects for animal feed. IR analysis results show that the pyrolysis led to conversion and/or removal of the vast majority of functional biomass groups, resulting in inorganic matter and inert carbon. The XPS analysis of the biochar indicates nitrogenous heteroaromatic structures which are formed during the pyrolysis process. In this way, can contribute to the cation exchange capacity in soils and adsorption of contaminants. Lastly, this biochar has great potential for use as an adsorbent for small molecules (due to the presence of micropores) after its activation, with a specific area of 1800 m2 g−1, surprisingly high compared with other solids of this type. Thus, a high value-added material can be obtained from the residue.

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.