Pirólise da casca da castanha-do-brasil : um novo arranjo experimental em reator induzido por micro-ondas (2,45 GHz)

Abstract

The demand for renewable energy sources has increased in recent years, fluctuations in the oil market and the high rate of emission of natural pollutants have been the trigger for the development of new researches which aim to discard the use of oil. In such a way that the treatment of residues and biomass has been promising within this problem. Biomass pyrolysis allows obtaining products such as volatilized hydrocarbons, oxygenated organic compounds and carbon compounds which may be objects of interest in the chemical industry. In this context, this research aims to analyze a new experimental arrangement as a proposal for the pyrolysis of the Brazil Nut bark assisted in a microwave reactor (2.45 GHz) and the determination of the temperature profile during this process pyrolytic. In the experimental arrangement discussed, the gases from the pyrolysis were separated and condensed by the lower portion of the reactor, which was machined with two thermocouple type thermometers to determine the temperature during the reaction. The results obtained indicated that the exit through the lower portion of the reactor is not feasible due to the high possibility of system clogging and the resistance of the gases, which results in the loss of bio-oil and gases through leaks, even in the absence of a mechanical stirrer. , with N2 inert gas flow and solid separation mesh. Regarding the temperature, it was possible to observe that the pyrolysis temperature reached 465-570ºC at the critical moments of the experiment, later stabilizing in the range of 330-350ºC when the biochar was obtained. The obtained products, bio-oil and bio-char were characterized by 1H and 13C nuclear magnetic resonance (NMR) techniques and by Fourier transform infrared spectroscopy (FTIR) which made it possible to observe the presence of oxygenated organic compounds and unsaturated aromatics in the bio-oil.