Waste cooking oil as a viable source of biodiesel in metropolitan cities

The development of a country is directly linked with its natural resources of energy. The fossil fuels are getting depleted and the environmental issues have energized the development of alternative energy sources. Biodiesel from non-edible oils play an important role in this aspect. Waste cooking oil is one of the alternative sources of biodiesel. The metropolitan cities like Bangalore have large number of restaurants and produce over 20,000 L of waste cooking oil every day. Biodiesel production has been carried out adopting a two stage process, involving acid esterification and alkali catalyzed transesterification. Transesterification was carried out using 1:6 oil to methanol molar ratio at 60 °C for 60 minutes. The density and viscosity of waste cooking oil reduced from 917.41 Kg/m3 to 879.10 Kg/m3 and 43.5 mm2/s to 4.99 mm2/s respectively by transesterification process. There was improvement in calorific value of oil from 32.5 MJ/kg to 34.2 MJ/kg of biodiesel.