poster - International Conference of Agricultural Engineering

Figure 2-Relationship between the viscosity of the castor oil plant genotype BRS Energia and
temperature interaction significant at 1% significance level. Campina Grande, Paraíba,
Brazil.
The wild one material (Equation 4) suffered loss in viscosity at a temperature even lower,
possibly because the lower content of fatty acids contained in oil of this genotype, although
not measured.
Equation: y = 8863445,00 – 84494,0x + 267,461x 2 – 0,2811x 3 (4)
R 2 = 0,9366
According CHIERICE NETO AND CLEAR (2001) the specific behavior of castor oil in the
face of variable density and viscosity is due to the strong presence of ricinoleic acid
(approximately 89.5%) in the oil composition, the molecule of this acid has 18 carbon atoms
with three functional groups: the terminal carboxylic group, the double bond in the 9th carbon
and the hydroxyl group at the 12th carbon. This structure of ricinoleic acid is also responsible
for the solubility of castor oil in ethanol at normal temperature and pressure conditions
(CNTP), it differing from the other vegetable oils. This high viscosity is interesting for some
industrial applications, their use as lubricant, and is not good for others, their use as
biodiesel, but this oil does not preclude such use, because now you can mix oils to obtain
various types biodiesel that meets national specifications (ANP) and international oil and
castor oil can enter up to 40% without problems in a mixture of mineral diesel.
Specific Heat
The average values of specific heat of genotype BRS Energia (0.3653 cal/g ºC) showed a
significant difference at 5% probability by Tukey test, when compared to Wild genotypes
(0.2792 cal/g °C) and BRS Paraguaçu (0.2742 cal/g °C), consisting higher heat capacity, to
easily gain and heat loss without significant changes in temperature of the oil, which is
important for industrial use. The larger the specific heat more heat energy can be retained
without great increase in temperature.