DANTAS, R. D. B. C.; http://lattes.cnpq.br/5238072689355487; DANTAS, Rodrigo Dias de Bivar da Câmara.
Resumen:
Biodiesel derived from the frying oil contributes to a reduction of greenhouse gases in the
atmosphere and minimizes the disposal of waste oil into the environment. This workmaims to
characterize and evaluate the thermal stability of alkaline transesterification of biodiesel from
the frying oil routes methyl and ethyl. The samples were characterized through physicochemical,
spectroscopic, chromatographic and thermal analysis. In the process of getting the
biodiesel from frying oil, the reaction rate and methyl ethyl routes were 95% and 94%
respectively. The physicochemical properties indicated that all parameters for methyl and
ethyl biodieseis from the frying oil met the demands of the limits established by the Technical
Regulation No. 1 / 2008 of the National Agency of Petroleum, Natural Gas and Biofuels
(ANP), except ester content. The chromatographic data confirmed the conversion of used
frying oil into esters, indicating conversion to ester content of 90.1 % of biodiesel methyl,
below the limit established by the Technical Regulation of ANP (96.5%), indicating the need
to improve the synthesis process. The infrared spectra showed the main absorption bands of
methyl and ethyl biodiesel from used frying oil and their respective functional groups and
show that both biodieseis showed low humidity. Thermogravimetric curves (TG) of samples
of frying oil biodiesel showed two stages of mass loss attributed to the processes of
volatilization and/or decomposition of esters, particularly their major components linoleate
and oleate indicated by chromatography. Comparing the samples it appears that biodiesel
methyl was more stable than the ethyl biodiesel. Biodiesel methyl remained thermally stable
up to 143 0 C ethanol and biodiesel to 122 ° C. The curves of differential thermal analysis
(DTA) of biodieseis observed four exothermic transitions attributed to the combustion process
of the esters. Although derived from frying oil waste, the methyl and ethyl biodieseis showed
satisfactory results regarding the characterization and thermal stability.