 Good morning to one and all. Today, we are going to learn about fuel in that biodiesel. So, at the end of this session, students will be able to explain the synthesis and advantages and disadvantages of a biodiesel. So, content of today's lecture will discuss about definition of fuel, biodiesel, its synthesis, advantages and disadvantages. So, introduction fuel. Fuel is any combustible substance containing carbon as a main constituent, which on proper burning gives large amount of heat, which can be used economically for domestic and industrial purposes. During the process of combustion of fuel, the atoms of carbon, hydrogen, prompure combine with oxygen with simultaneous liberation of heat at a rapid rate. This can be explained with this particular reaction. So, fuel when it combines with oxygen that is when undergoes combustion process, it forms a product as well as heat. So, the fuel contains more heat energy whereas the product is having a lesser heat energy and heat is liberated that is being used in our day to day practices biodiesel. Biodiesel is an alternative fuel similar to conventional or fossil diesel. Biodiesel can be produced from vegetable oil, animal oil, fats like tallow or waste cooking oil. The process used to convert these oils to biodiesel is called transesterification. Biodiesel has many environmentally beneficial properties. So, synthesis of biodiesel, biodiesel is synthesized with various steps. Vegetable oil and animal fats are basically triglycerides. They contain triglyceride molecules. They are fatty acid esters of single alcohol glycerol. Vegetable oil and animal fats have a very high viscosity and they cannot be used directly as a fuel. Thus, by transesterification reaction the triglycerides can be converted into their methyl or ethyl esters having less viscosity, oil and fats. These ethyl or methyl esters can be used as biodiesel. Biodiesel is a renewable source of energy having low pollution potential than conventional diesel. It can be used in diesel engine as a substitute to conventional diesel or a blend of diesel and biodiesel is used. Reaction to explain this particular formation of methyl ester that is biodiesel. This is a triglyceride from oil or fats when it is treated with methyl alcohol either or ethyl alcohol in presence of acid or base as a catalyst. The reaction occurs the glycerol is formed and methyl esters are also formed. So, this reaction occurs likewise the methyl alcohol break opens and forms methyl and hydroxyl groups. These radicals attacks the carbon of triglycerides. So, this forms CH2OH. OH comes from this particular methanol and this CH2OH, CHOH and CH2OH this glycerol is formed. Whereas, methyl group gets attached to this oxygen of triglycerides. So, R-COO and CH3. So, in short this is R-C double bond OH OH CH3 such a molecule is formed this is methyl ester and that is being used as a biodiesel. Compared to the other alternative fuels biodiesel fuel supports some unique features and qualities. Unlike any other alternative fuels it has successfully passed all the health effects testing requirements meeting the standards of 1990 clean air act amendments. So, what are the advantages of this biodiesel? First advantage biodiesel fuel is a renewable energy source unlike petroleum based diesel. An excessive production of a soya bean in the world makes it an economic way to utilize the surplus for manufacturing to the biodiesel. Third one of the main biodiesel fuel advantage is that it is less polluting than petroleum diesel. So, pollution is the most important parameter of our today's life and this biodiesel is reducing the pollution parameter. Fourth, the lack of sulfur is 100% in biodiesel extends the life of catalytic converters. Another advantage of biodiesel fuel is that it can also be blended with the other energy resources and oil. Sixth biodiesel fuel can also be used in existing oil heating systems and diesel engine without making any alteration. Sixth, it can also distribute through existing diesel fuel pumps which is another biodiesel fuel advantage or other alternative fuels. The lubricating property of the biodiesel may lend them the lifetime of an engine. So, at this moment pause the video and answer this question. The question is by trans-sterification reaction the triglycerides can be converted into their methyl or ethyl esters having dash dash options A less viscosity oils and fats B very high viscosity oil and fats C moderate viscosity index and D none of this. Welcome back the answer for this question is A less viscosity oil and fats. So, disadvantages of biodiesel first cost at present biodiesel fuel is about one and half times more expensive than petroleum diesel fuel. It requires energy to produce biodiesel fuel from soya crops plus there is the energy of sowing fertilizing and harvesting etc. This will increase the cost of this particular product. Third another disadvantage is that it can harm rubber hoses which are used in some engines. Fourth as biodiesel cleans the dirt from the engine this dirt can then get collected in the fuel filter thus clogging it. So, filters have to be changed after the first several hours of a biodiesel use. References for this particular lecture I have used a textbook of a Gen Engineering Chemistry by Jane and Jane. Thank you.