Assessing thermal and optical properties of biodiesel by thermal lens spectrometry: Theoretical and experimental aspects

作者:Savi Elton L; Herculano Leandro S*; Lukasievicz Gustavo V B; Regatieri Helton R; Torquato Alex S; Malacarne Luis C; Astrath Nelson G C
来源:Fuel, 2018, 217: 404-408.
DOI:10.1016/j.fuel.2017.12.104

摘要

Recent studies on laser induced thermal lens effect has made it possible to use this tool to investigate thermo-physical and chemical properties of biofuels. During laser illumination, a number of light induced effects may take place in the excited volume of the sample. However, the complexity of information included in the thermal lens transients could lead to misinterpretation of the results. This work examines the theoretical and experimental aspects that must be considered when performing biodiesel analysis using thermal lens spectrometry. The induction of photochemical reaction and thermal diffusion processes is carefully accounted for by describing the localized optical path change due to the concentration gradient created within the sample. We characterize mechanical, chemical and photochemical properties of thermal degraded biodiesels, enabling quantitative access of mass diffusion coefficient, photobleaching cross-section, and thermal yield. Dynamic viscosity analysis corroborates the results obtained by thermal lens, describing the method as very sensitive to thermal stability discrimination of biodiesel.

  • 出版日期2018-4-1