TITLE:
Production of Biodiesel with Seed Soybean and Supercritical Ethanol
AUTHORS:
Gabriel Cassemiro Mariano, Toni Jefferson Lopes, Rafael Dias, Marintho Bastos Quadri, Ariovaldo Bolzan
KEYWORDS:
Supercritical, Biodiesel, Non-Catalytic Transesterification, Ethyl Ester, Soybean Seed
JOURNAL NAME:
Journal of Sustainable Bioenergy Systems,
Vol.4 No.2,
June
5,
2014
ABSTRACT: This paper presents a study of biodiesel production by a non-catalytical
process. The innovation in this study is the use of novel materials for
production: seed soybean (Glycine Max) “in natura” and ethanol in a
supercritical state. To conduct the experiments, a bench reactor with a
capacity of 150 mL, resistant to pressure of up to 300 bar and temperature of
350°C was developed. The fractional factorial experimental design () was used to evaluate
the temperature, seed granulometry, molar ratio ethanol/oil and water percent
of the mixture. The best yield observed
was that of 94.07%, 10 minutes after the reactor entered a supercritical
condition. Significant effects on seed granulometry, molar ratio ethanol, oil
and temperature were verified. From the proposed
process, biodiesel and toasted soybean seed were obtained. To purify the
biodiesel sample it was necessary to use ultra-centrifugation to separate seed
particles, and rotoevaporation to separate the fatty acid ethyl ester and
unreacted ethanol. The chemical analyses were conducted directly by gas
chromatography. The yield was calculated in accordance with concentrations
obtained in the chromatographic analysis and seed mass of the experiment. Also
checked was the presence of palmitate esters, stearate, oleate, linoleate and
linolenate. By analyzing the ester
composition it was possible to assess whether a good quality biodiesel was
available. The roasted soybean seeds obtained after the reaction showed a
calorific potential of 2203.17 kcal/kg and also be used as fuel.