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 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.