OPTIMIZATION OF BIODIESEL PRODUCTION FROM SUNFLOWER OIL USING RESPONSE SURFACE METHODOLOGY

1. Realizado por: Juan Carlos Meneses
Porlamar, noviembre de 2015

2. Vegetable oil is one of the renewable fuels which have become more attractive
recently because of its environmental benefits and the fact that it is made from
renewable resources. Vegetable oil has too high a viscosity for use in most
existing Diesel engines as a straight replacement fuel oil. One of the most
common methods used to reduce oil viscosity in the biodiesel industry is called
transesterification. Many of researchers have studied the transesterification for
production of biodiesel. These studies show that transesterification consists of
a number of consecutive, reversible reactions. Triglycerides are first reduced to
diglycerides. The diglycerides are subsequently reduced to monoglycerides.
Optimum conditions for the transesterification of vegetable oils to produce
methyl ester were determined by the previous researchers which yielded a
maximum conversion of various oils to the methyl esters. The conventional
catalysts used for transesterification are acids and alkali, both liquid and
heterogeneous, depending on the oil used for biodiesel production.
The use of acid catalysts has been found to be useful for pretreating high free
fatty acid feedstocks but the reaction rates for converting triglycerides to methyl
esters are very slow.
Realizado por: Juan Carlos Meneses

3. Several types of oils can be used for production of biodiesels. The
most common types of oils are sunflower oil. The batch reaction
kinetic experiments were employed to optimize various parameters
in the production of the methyl esters. The transesterification
reactions are performed in various conditions to determine the
optimum conditions of transesterification.
The high regression coefficients of the secondorder polynomial
showed that the model was well fitted to the experimental data.
The ANOVA implied that molar ratio of alcohol to oil; reaction
temperature and concentration of catalyst have the great
significant factor affecting the yield of biodiesel.
Realizado por: Juan Carlos Meneses

4. A few works reported the reaction at room temperature; most of
the researches have focused on the transesterification at near
boiling point of alcohol. Temperature has an important influence
on speed of reaction and led to higher conversion of ester. With
increasing temperature of reaction, yield of biodiesel increased
quickly to near the boiling point of alcohol. At low temperatures,
relatively low conversion to methyl ester evident due to the
subcritical state of methanol. At higher temperature than boiling
point of methanol, alcohol evaporates and the yield was
decreased.
The biodiesel production has a negative quadratic behavior by
temperature, molar ratio of alcohol to oil and concentration of
catalyst. It was predicted that the optimum reaction condition
within the experimental range would be the molar ratio of 6.825:1
and temperature of 48°C and concentration of KOH equal to
0.679wt%. At the optimum condition we can reach to yield of
98.181%.
Realizado por: Juan Carlos Meneses