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Student Projects/Why biodiesel can save the earth?

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Introduction:

Global warming is the most pressing issue across the globe. The main cause of global warming is the emission of greenhouse gases into the atmosphere. The major source of these greenhouse gases are from the burning of fossil fuels (petrol, diesel, coal, etc). So as an alternative to these traditional fossil fuel there is something called bio fuels. Which are derived from biological sources and will have less emission of greenhouse gases when compared to traditional fuels. The physical properties of biofuels like calorific value, density is the same as that of the conventional fuel. Moreover this bio fuels are derived from renewable resources like plants so it prevents our dependency on more demanding and exponentially depleting non renewable resources like petrol, diesel. So replacing normal conventional diesel with bio diesel not only healthy for the environment but also healthy for the economy as it reduced the dependence of ever changing price of conventional oil which is determined internationally and it also improves the self-sustainability. Addition to that it doesn’t need any modification in engines that uses the conventional fuel. Bio diesel could be directly used in the engines that powered by conventional fuels that are already in use.

Bio-diesel:

Among the various known methods of bio diesel production, production of bio diesel via transesterification of oil (from plant and animal source) is the most favourable method. In this

method the oil is collected from various available sources and are trans-esterified with alcohol in suitable conditions to yield bio diesel.

Esterification:

To understand what is transesterification on must need to understand what is esterification first . Esters are smelly compounds, maybe the scent that you may contain esters. Among the various methods of producing ester chemically transesterification is one of the methods to produce it.It is produced when a carboxylic acid reacts with an alcohol in the presence of an

acid or a base to give an ester.

Transesterification:

Similarly the reverse reaction where the ester is hydrolysed (breaking with water) by acid/base to yield corresponding acid and alcohol, this reverse reaction is called as ester hydrolysis. If the same ester is lysed with an alcohol then the reaction is called as alcoholysis or transesterification

Need for Transesterification:

Vegetable oil or oil from animal source exists as thick triglycerides. They have almost all the similar properties like diesel but they are very denser than the normal diesel which make them

incompatible for direct use in diesel engines. So the transesterification reduces the density of triglycerides by converting them into monoglycerides(methyl ester) which are nothing but

bio-diesel, which can be directly used in existing engines. So each molecule of triglyceride can be converted into three molecules of methyl ester. So more hopefully, the production of bio diesel by transesterification may be one of the solutions to stop global warming and protect the environment.