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Os resíduos de coco representam um grande passivo ambiental nas regiões costeiras do Brasil em especial no Nordeste. Neste trabalho foi realizada a otimização do processo de pirólise deste resíduo para a geração de bio-óleo e biochar, que são os principais produtos da pirólise, reduzindo assim seu impacto ambiental e propondo formas de agregar valor aos resíduos de coco. Primeiramente a composição qualitativa e semi-quantitativa do bio-óleo foi determinada por GC×GC/qMS, apresentando elevada quantidade de compostos fenólicos, de alto valor agregado. Na sequência, o biochar foi caracterizado e testado como catalisador na produção de um bio-óleo com melhor composição química. A melhor condição de pirólise catalítica estudada foi utilizando 5% do biochar, aumentando em cerca de 75% no seu valor agregado aproximado, indicando a viabilidade de implementação de uma biorrefinaria baseada nos resíduos da agroindústria, em especial as cascas de coco verde. Desenvolveu-se também o primeiro método de fast-GC×GC, combinado com detector de espectrometria de massas por tempo de voo (TOFMS) para analisar a amostras de bio-óleo, o qual apresentou um aumento no sinal cromatográfico e redução do ruído. O fast-GC×GC manteve todas as informações cromatográficas obtidas por GC×GC convencional, reduzindo drasticamente o tempo total de análise. Por fim, usando o método de fast-GC×GC otimizado, avaliou-se o efeito na variação da taxa de aquisição de dados sobre o resultado analítico, concluindo que, sob condições de fast-GC×GC/TOFMS, é importante usar taxas de aquisição mais altas (200-300 Hz), levando a melhoria na reconstrução do pico e a uma melhor caracterização da amostra. Coconut waste represents a major environmental liability in the coastal regions of Brazil, especially in the Northeast. In this work, the pyrolysis process of this residue was optimized for the generation of bio-oil and biochar, which are the main products of pyrolysis, thus reducing its environmental impact and proposing ways to add value to these materials. Firstly, the qualitative and semi-quantitative composition of the bio-oil was determined by GC×GC/qMS, finding high amount of phenolic compounds, with high added value. Following this, the biochar was characterized and tested as a catalyst in the production of a bio-oil with better chemical composition. The best catalytic pyrolysis condition studied was 5% biochar, increasing 75% its approximated added value, indicating the feasibility of implementing a biorefinery based on agroindustry residues, especially green coconut shells. Subsequently, the first fast-GC×GC method combined with a time-of-flight mass spectrometer (TOFMS) was developed to analyze bio-oil samples, which showed an increase of the chromatographic signal and noise reduction. The fast-GC×GC maintained all chromatographic information obtained by conventional GC×GC, dramatically reducing the total analysis time. Finally, using the optimized fast-GC×GC method, it was evaluated the effect of data acquisition rate on the analytical result, concluding that on fast-GC×GC/TOFMS, it is important to use high acquisition rates (200-300 Hz), improving peak reconstruction and producing better sample characterization.

The biochar is characterized by low surface area and, in order to their use as adsorbent it is possible to use the activation process that allows to liberate and to increase the pores of the surface, increasing its sorption capacity. In the present work the activation of the biochar produced in the pyrolysis of agroindustrial residue (fiber) of the green coconut was studied, being done with sodium carbonate (Na2CO3) at high temperature. Biochar (BC) and activated biochar (ABC) were characterized and ABC was tested for use in the extraction of organic compounds present in the phenolic liquor, produced during the same pyrolysis process. The determination of the textural characteristics was done by N2 adsorption-desorption isotherms, obtaining an area of 1130 m2 g−1 for the ABC, being superior to the area of commercial activated coals, with a total volume of pores of 0.55 cm3 g−1. For the solid phase extraction (SPE) test, 500 mg of ABC were used in cartridges (equal to the commercial ones) obtaining a retention of about 100% of the organic compounds pre-existing in the sample, demonstrating the high adsorptive capacity of the activated biochar produced in this work. Desorption, as expected, had a lower performance than adsorption, being improved using ultrasonic bath, reaching values of the order of 40% recovery.