Investigation of the thermal degradation of the biolubricant through TG-FTIR and characterization of the biodiesel - Pequi (Caryocar brasiliensis) as energetic raw material

摘要

This work reports the obtaining of the methyl derivative - BP1 (biodiesel) and trimethylolpropyl derivative BP2 (biolubricant) of the pequi oil -OP, its characterization and evaluation of the thermal degradation of the trimethylolpropyl derivative through thermogravimetric analysis in conjunction with Fourier transform (TG-FTIR). Biodiesel was prepared through homogeneous methyl route and potassium hydroxide as catalyst. Biolubricant was prepared using trimethylolpropane and biodiesel (1/4M ratio) and sodium methoxide as catalyst. Spectroscopy techniques such as infrared with Fourier transform (FT-IR), and nuclear magnetic resonance of hydrogen and carbon (NMR H-1 and C-13) were used in the analysis of the products. Physicochemical properties such as acid number, iodine number, specific mass, and kinematic viscosity were also determined under international standard. Thermogravimetric analysis of the pequi biodiesel was performed in three different heating rates in order to evaluate the activation energy of the biodiesel by using the method proposed by Flynn-Wall-Ozawa, and the value found was 67.07 kJ.mol(-1). For the biolubricant, the thermogravimetric analysis in conjunction with Fourier transform (TG-FTIR) provided interesting comprehension of the oxidation process for trimethylolpropyl esters, describing the steps of volatilization and combustion.