Caracterização para múltiplos usos do pecíolo de Mauritia flexuosa L.f.

Abstract

The Palm trees, like the Mauritia flexuosa (buriti), is composed by one of the groups of plants of great social and economic importance for the Amazon region. However, despite the cultural and economic importance of M. flexuosa, it is still unexplored its technological potential for multiple uses. Thus, the objective of this work is to characterize the petiole of M. flexuosa to indicate potentials of the species for coal and energy production and application as biomaterial. A comparative characterization was performed between core and bark of petiole of buriti involving chemical composition, density, calorific power and thermogravimetric analysis for coal production purposes and combustion. The potential of the core of the petiole in the natural condition and thermally modified at 180°C, for 1 h (60 min) and 2:30 h (150 min), was verified by molecular chemistry, index of crystallinity, physical resistance and mechanical resistance. The bark presented higher density, moisture and low volatile content in comparison to the core. But the core had higher ash content, lower fixed carbon content and lower calorific higher. Thermogravimetric analysis showed a greater resistance to thermal degradation and less mass loss of the shell when compared to the core. Therefore, the bark has greater potential for power generation and coal, which is advantageous because it is a residue destined firom core to other uses, such as handicrafts. The chemical composition of the petiole natural presented higher amounts Holocellulose 78.38% (Cellulose 68.45% + hemicelluloses 9,935), followed by lignin with 19.2%, extractives 8.88% and inorganics 2.05%. With application of the heat treatment there was a decrease the crystallinity index caused by the thermal degradation of the cellulose. The heat-treated petiole became less hygroscopic and more stable dimensionally, demonstrating that the treatments at 180°C are efficient in improving the physical properties evaluated. However, the mechanical properties were negatively affected by the increase of heat treatment time, reducing the resistance to compression of the M.flexuosa specie.