Charcoal has a large share in the Brazilian market. The production is carried out by pyrolysis of biomass at different temperatures, between 300 and 500 °C. In this study, the corn cob pyrolysis was investigated using thermogravimetric analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). Samples after pyrolysis were compared with raw biomass to evaluate changes in fuel characteristics. In DTG curves a reduction in the number of degradation peaks in the carbonized material was observed. The FTIR spectra allowed to identify the aromatic ring of the lignin in the charcoals structure, indicating the presence of this compound even in charcoals produced with a temperature of 500 °C. It can be concluded that the temperature of 400 °C was enough to completely degrade the hemicellulose and cellulose of the biomass, resulting the final product (charcoal) less reactive or thermally more resistant than the in natura corn cob.

ABSTRACT The aim of this study was to apply geostatistics to predict the spatial pattern of variations in moisture content of eucalyptus wood chip piles to generate subsidies for adequate sampling and material handling. Wood chip piles were installed in three different storage cycles using newly cut material for 7, 30, and 60 days. Sampling was performed in axial (top, middle, and base) and lateral positions, so that all samples were georeferenced in relation to the distance from the ground and the center of the pile. Moisture values were submitted to geostatistical analysis and kriging. The results confirmed the spatial dependence of moisture content over the piles stored at 7 and 30 days; however, the effect of rainfall was crucial to reduce the spatial dependence of moisture content. The results showed that geostatistics is a useful tool for the creation of reliable sampling protocols.

ABSTRACT This work aims at the physicochemical characterization of four species: Eucalyptus sp, Pinus sp, Citrus sinensis and Hevea brasiliensis for use in ceramic furnace. Immediate analysis, chemical analyses were carried out (total extractives, Klason lignin, holocellulose and alpha-cellulose content). Results were applied to ANOVA and Tukey for statistics. The ash content of Pinus sp was 1.60%, for volatile material content Eucalyptus sp presented 83.61%, for fixed carbon values, Citrus sinensis presented 20.03%. Chemical analyses in the total extractive content, Citrus sinensis presented 21.76%, Klason lignin content, Pinus sp had 39.24%, Eucalyptus sp 60.29% had the highest holocellulose and alpha-cellulose, which was 42.72%. Pinus sp sample was the one with the highest heating value of 20.090 J/g. According to results obtained in the analyses, it is possible to conclude that all species have potential for applications in ceramic furnace.

Eucalyptus bark is a waste generated in large volume and has been used as a source of energy. This study tries to use the Eucalyptus sp. bark as a source of raw material for the charcoal production and to study the influence of pyrolysis temperatures on charcoal properties. Charcoal was produced at different temperatures: 300, 400 and 500 °C, and their properties were determined by proximate analysis, higher heating value and thermogravimetric analysis. It was observed that higher pyrolysis temperature resulted in increase of the fixed carbon content and higher heating value. In the thermogravimetry and derivative thermogravimetry curves it was possible to determine the differences in the thermal stability of charcoal produced. It can be concluded that the eucalyptus bark charcoal is an alternative for the energy reutilization of this waste and also can be used as charcoal for heating.

RESUMO Uma alternativa como fonte para geração de energia é o uso de biocombustível sólido produzido pelo processo de briquetagem. O briquete é produzido pela compactação de materiais lignocelulósicos, possibilitando que haja maior energia em menor volume. O objetivo desse trabalho foi analisar a briquetagem do Schizolobium parahyba (guapuruvu), avaliando-se a estabilidade, densidade, resistência mecânica e friabilidade dos briquetes. Foram testados três granulometrias diferentes: tratamentos T1 (maior que 40 mesh), T2 (entre 40 e 60 mesh) e T3 (menor que 60 mesh), todos briquetados a um teor de umidade de 12%, utilizando-se prensa hidráulica sem o uso de aquecimento nem aglutinante. Os três tratamentos diferiram significativamente entre si quanto à densidade, expansão longitudinal e resistência à tração por compressão diametral. A granulometria mais fina (T3) apresentou os melhores resultados para todos os parâmetros, tendo os maiores valores para a densidade (0,932 g.cm-3) e resistência (0,485 MPa) e menor índice de friabilidade (8,35%). Os resultados mostraram que a granulometria interfere nas características do produto final. O estudo mostrou que o guapuruvu pode ser uma alternativa para a produção de biocombustível sólido.

ABSTRACT The use of solid biofuel produced by the briquetting process is an alternative source for power generation. The briquette is produced by the compression of lignocellulosic materials, allowing for a higher energy at a lower volume. This work aimed to study the briquetting process of Schizolobium parahyba (guapuruvu). It was evaluated the stability, density, mechanical resistance and friability of the briquettes. The treatments were: T1 (above 40 mesh), T2 (between 40 and 60 mesh) and T3 (below 60 mesh). All treatments were adjusted to a moisture content of 12%. The briquettes were produced by hydraulic press without using heat or binder. The three treatments were statistically different from each other in terms of density, height expansion and diametrical compression resistance. The treatment T3 showed the best results for all parameters, with the highest values for density (0.932 g.cm-3) and mechanical resistance (0.485 MPa). Also, T3 presented the lowest friability (8.35%). The results showed that the particle size interferes in the final product characteristics. The study showed that guapuruvu could be an alternative for solid biofuel production.

Pectin and starch are edible, non-toxic, biodegradable and obtained from renewable sources. Also, have the benefit to be easily cross-linked producing hydrogels. Reactive extrusion with edible citric acid and cross linking interactions was evaluated on extruded thermoplastic in natura and cationic starch-pectin blends. Materials water susceptibility and mechanical properties were characterised. Reactive extrusion decreased (up to 75% in natura starch) mechanical properties. Also have decreased (up to 32.4%) both starch polymers water absorption, indicating the possibility of increasing materials water barrier properties but had the opposite effect on the pectin-TPS material, probably related to a cationic-anionic cross linking, resulting in a hydrogel polymer. Reactive extrusion also have negatively affected mechanical properties of both starch polymers, however increased pectin-TPS blends stress and strain at rupture.