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This work studied fast pyrolysis as a way to use the residual fiber obtained from the shells of coconut ( Cocos nucifera L. var. Dwarf, from Aracaju, northeastern Brazil). The bio-oil produced by fast pyrolysis and the aqueous phase (formed during the pyrolysis) were characterized by GC/qMS and GC×GC/TOF-MS. Many oxygenated compounds such as phenols, aldehydes, and ketones were identified in the extracts obtained in both phases, with a high predominance of phenolic compounds, mainly alkylphenols. Eighty-one compounds were identified in the bio-oil and 42 in the aqueous phase using GC/qMS, and 95 and 68 in the same samples were identified by GC×GC/TOF-MS. The better performance of GC×GC/TOF-MS was due to the possibility of resolving some coeluted peaks in the one-dimension gas chromatography. Semiquantitative analysis of the samples verified that 59% of the area on the chromatogram of bio-oil is composed by phenols and 12% by aldehydes, mainly furfural. Using the same criterion, 77% of the organic compounds in the aqueous phase are phenols. Therefore, this preliminary assessment indicates that coconut fibers have the potential to be a cost-effective and promising alternative to obtain new products and minimize environmental impact.

The goal of this paper is the evaluation of fast two‐dimensional gas chromatography applied to bio‐oil samples. Bio‐oils are complex matrixes that usually are analyzed by conventional gas chromatography, involving long columns, long time of analysis due to slow heating rates, and consequently, high cost associated to time consumed. Fast gas chromatography techniques are based on the use of narrow capillary columns that allow the achievement high‐speed separations for complex samples, maintaining excellent resolution. Firstly, the two‐dimensional gas chromatography method was optimized varying the heating rate (10, 15 and 20°C min−1) and achieving the optimal separation at 15°C min−1. This method allies a good separation of bio‐oil constituents with shorter time analysis. The developed method and the traditional conventional two‐dimensional gas chromatography method (used in previous studies) were applied in the analysis of a mixture of 30 standard compounds. Despite coelutions of short retention time peaks (compounds with very similar physical‐chemical properties), the fast two‐dimensional gas chromatography method showed an increase in chromatographic signal and a noise reduction. Good results were also obtained in the real bio‐oil sample. Fast two‐dimensional gas chromatography maintained all the chromatographic information from conventional two‐dimensional gas chromatography, reducing drastically the total time of analysis.