Otimização da síntese e caracterização do biodiesel metílico e etílico do óleo de licuri (Syagrus coronata), e adição de ésteres metílicos como aditivo em blendas de biodiesel de soja

Abstract

This paper has as its goal to optimize the synthesis of biodiesel from Licicuri vegetal coconut oil and therefore increase the the yield and also improve its physiochemical characteristics to introduction and aplication of this new oleoginous as an alternative raw material in the production of biofuel in the Brazilian region of semi arid, adding a better sustentability too the national energetic matrix. Having this as a purpose, it was made mechanical continual extractions and purification (refine) of Licuri oil. Although this almond has 49,2% of lipid, this techinic presented from 48,0 % of yield, becoming highly viable for the biosiesel production. This research optimized the transesterification through methyl and ethyl routes in basic catalysis and room temperature with constant stirring, reaching the best yield in biodiesel mass with methanol and ethanol oil of 1:10, 1% of KOH and reaction time of 120 minutes. Under these conditions, the methyl and ethyl biodiesel presented a yield of 96,7% and 91% respectively. Later the oil and the biodiesel were subjected to its physiochemical characteristic analysis (relative density, acid level, refractive level, kinemectic viscosity, thermogravimetric and oxidative stability), according to the Brazilian specifications (ANP), ASTM D6751 (American Society of Testing Materials) and European EN 14214. In relation to the stability of the product oxidation, the licury oil presented more than 48 hours under oxidative conditions of analysis in Rancimat, showing execellent antioxidant properties. The methyl biodiesel presented 23 hours of oxidative induction, values within the specifications. The ethyl biodiesel presented only 7 hours, however the biodiesel analysed is the B100 and not mixed in diesel as the current commercial amount for combustion engines. Due to the high stability of the methyl esters and due to its carbon chains being greatly saturated, this was added and tested as an additive in soy methyl biodiesel of low oxidation stability to increase the oxidation time in soy biodiesel, giving to it a better quality, durability and storing time. According to the results, this raw material proved very promising for the production of methyl and ethyl biodiesel, demonstrating its high quality and stability, besides the use of the methyl esters as an additive.