The objective of this work was to study the process of bio-oil production through the pyrolysis
of raw acai kernel on a pilot scale, focusing on the yield of products obtained at temperatures
of 350°C, 400°C and 450°C at 1 atm. In addition to studying the results obtained via gas
chromatography coupled to mass spectrometry (GC-MS) of the bio-oils produced. For the
experimental procedure, the raw material used was the açaí pits, a residue obtained after the
process of pulping the fruit. This material went through stages of drying, comminution and
sieving to remove unwanted residues for the process. This material was characterized by
determining the moisture content, volatile content, ash content, fixed carbon content and higher
calorific value. After the characterization process, the lumps were submitted to the pyrolysis
process and, after the due separation processes, the bio-oil obtained was submitted to tests to
determine its acidity index, absolute density, refractive index, and dynamic viscosity. After this
step the bio-oil was subjected to analysis in a gas chromatograph coupled to a mass
spectrometer. The moisture content found in the açaí seeds was approximately 40% and the
yield of the pre-treatment step was 46.84%. In the physical characterization of the seeds the
results found were within the existing literature showing interesting properties for use in the
pyrolysis process. With the increase in temperature there was a favorable production of bio-oil
and biogas, while for the biochar there was a decrease in its mass produced. The physicalchemical analyses applied to the Bio-Oil produced were within the values that are available in
the literature for this same type of material, however, it is still outside the standards that the
National Petroleum Agency establishes for green diesel. The increase in temperature reduced
the acidity of the bio-oil and increased its viscosity and density. With this, there was a reduction
92.87 (Exp.1) to 70.26 (mg of NaOH/g of sample) (Exp.3) and the lowest kinematic viscosity
obtained of 77.62 mm²/s for the pyrolysis process with the temperature set up to 350°C. The
chromatographic analysis showed that the compound with the highest percentage of peak area
was phenol, where the average retention time was 8,466 min-1 independent of the programmed
temperature. Exp.2 had the highest yield in terms of aromatic hydrocarbons and the lowest yield
for phenols, showing that there is no linear behavior with temperature change.
|
