Energy shortage is serious problem in many countries more than 50% of foreign currency earned by India is lost in importing crude. Import dependence of the oil in India is presently about 70% is likely to increase in next few years by multiple. The share of hydrocarbon in the primary energy consumption of country has been increased over a year & is presently is estimated at 44.9%(36% of oil & 8.9% of natural gas.).The demand for oil in India is expected to grow at an average rate of 3.6% over a next five year, which will be higher than the average growth rate of around 2% in the world. All these things promote us to think about an alternate fuel.
Biodiesel is an alternative fuel chiefly made from vegetable oil. It can act both as substitute & an additive to diesel fuel. US department of energy estimated that up to 50% of he diesel fuel could be replaced with biodiesel. Importance of biodiesel increases due to increasing petroleum prices, limited fossil fuel resources & environmental benefits of biodiesel.
Base catalyzed transesterification is the process by which biodiesel can be manufactured economically. Biodiesel manufactured by this process has heat content of 90% of diesel. The engine performance with biodiesel is similar to that of diesel while the emission of carbon dioxide is lowered to 28% as compared to diesel. Because of use of non-edible oil as row material the economics of process increases. In this process >97% of conversion can be achieved, the optimizing parameter of the process are discussed in this paper, I also tried to focus on an engine performance with the biodiesel.
The title of my paper signifies the need of innovation & its implication in today’s world so as to make this world safer place to life.
Import dependence for oil in India, which is about 70%, is likely to increase further with increasing population rate which forces us to thought about the alternative sources of energy.
Biodiesel is produced from the wild oil seed plant (pongamia pinnata) which can easily be grown on wastelands, it is promising one for sustaining availability of raw material feedstock for biodiesel production. Government of India is planning to grow oilseed plant like pongamia pinnata in cultivated wasteland area of about 175Mha.
Biodiesel is the alkyl ester obtained by base catalyzed transesterification of the vegetable oil acts as an alternative fuel to diesel. Biodiesel has gained more importance in the past few years due to the depletion of world’s petroleum reserves.
Base transesterification is a kind of organic reaction in which alkaline metal hydroxide are acts as a catalyst, where alcohol group in ester is substituted. In this reaction the vegetable oils, the triglyceride reacts with three molecules of alcohols in presence of the catalyst producing the mixture of fatty acids, alkyl esters & glycerol.
BASE CATALYZED TRANSESTIRIFICATION :-
In the transesterification of vegetable oils, a triglyceride reacts with an alcohol in the presence of a strong acid or base, producing a mixture of fatty acids alkyl esters and glycerol. The overall process is a sequence of three consecutive and reversible reactions, in which dimonoglycerides and monoglycerides are formed as intermediates. The stoichiometric reaction requires 1 mol of a triglyceride and 3 mol of the alcohol. However, an excess of the alcohol is used to increase the yields of the alkyl esters and to allow its phase separation from the glycerol formed Several aspects, including the type of catalyst (alkaline or acid), alcohol/vegetable oil molar ratio, temperature, purity of the reactants (mainly water content) and free fatty acid content have an influence on the course of the transesterification.
Conversion of vegetable oil to biodiesel is effected by several parameters namely
Time of reaction
Reactant ratio (Molar ratio of alcohol to vegetable oil),
Types of catalyst, and
Temperature of reaction.
Transesterification or alcoholysis is the displacement of alcohol from an ester . Transesterification is one of the reversible reactions & proceeds essentially by mixing the reactants. However the presence of catalyst (KOH or NaOH) accelerate the conversion. The general reaction of transesterification is shown below.
EXPERIMENTAL SETUP :-
Reaction or transesterifaction was carried out in a system, as shown in Figure. Reactor consisted of spherical flask, which was put inside the heat jacket. Oil was used as medium of heat transfer from heat jacket to the reactor. Thermostat was a part of heat jacket, which maintain the temperature of oil and in turn the temperature of the reactants at a desired value. The reaction was carried at around 65-70 oC. Spherical flask consisted of four openings. The center one was used for putting stirrer in the reactor. The motor propelled the stirrer. Thermometer was put inside the second opening to continuously monitor the temperature of the reaction. Alcohol was vaporized during the reaction so the condenser was put in the third opening to reflux the vapors back to the reactor to prevent any reactant loss. Fourth opening was used for filling reactants to the reactor
EXCREMENTAL PROCEDURE :-
A Known quantity of used karanja oil (100ml for each run)) was taken inside the reactor and heated at about 70oC. This temperature is maintained throughout the reaction by the thermostat inside the heat jacket. Preheating was used to remove unwanted moisture present in the oil. The transesterification was carried out in basic medium and to achieve it, Lipase was used as catalyst. Catalyst was dissolved in methanol. Once the oil temperature reached 70oC, alcohol solution (containing dissolved catalyst) was added to the reactor and an equilibrium temperature was maintained. During the reaction alcohol gets vaporized. To prevent any reactant loss condenser was used to condese the alcohol vapor and reflux it back into the reactor. Condenser is also helpful to maintain atmospheric pressure inside the reactor.
Once reaction was over the products were taken out through the outlet in the lower side of the reactor and put in the separating funnel. Two phases(having different densities) are formed as a result of transesterification. Separation was done using separating funnel (separation took around two hours). Upper layer consist of biodiesel, alcohol, and some soap. Lower layer consisted of glycerin, excess alcohol, catalyst, impurities, and traces of un reacted oil.
Purification of upper layer (to obtain biodiesel) was done in two steps.
(i). Removal of alcohol – by keeping mixture at elevated temperature 80oC
(ii) Removal saponified products – by washing with warm water. Water is immiscible with biodiesel, hence can be easily separated from biodiesel.
Next related post :-INDUSTRIAL PRODUCTION PROCESS OF BIODIESEL
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