Characterization of Biodiesel Derived from Crude Oil of Pongamia sps. Grown in Tumkur District, India

Abstract

INTRODUCTIONThe methyl or ethyl esters of fatty acid are derived from the both edible and non-edible vegetable oils followed by animal fats which are termed as biodiesel. The chief sources for obtaining biodiesel particularly in India are categorized as non-edible oils of plant species such as Pongamia sps., Jatropha curcas (Ratanjyot), Calophyllum inophyllum (Nag-champa) followed by rubber yielding tree called Hevea brasiliensis, respectively. The biodiesel basically comprising of no petroleum constituents, even though it can be subjected for blending with petroleum diesel at any level to produce variable blends of biodiesel with petroleum diesel or in some instance, the biodiesel can be used in its pure form to serve the purpose [1][2][3][4].There is a significant reduction of unburnt hydrocarbons like carbon monoxide, particulate matters followed by nitrogen oxide in the existing internal combustion engine system fuelled Pongamia is non-edible oil which contains several toxic and unsaponifiable components. The presence of these multifarious compositions makes the oil unsuitable for human consumption. However, Pongamia has high oil content (~ 40 %) and can grow on malnourished soils with low levels of nitrogen and high levels of salt, which prompts in becoming the focus of a number of biodiesel research programs. Generally, the oil is contaminated with high free fatty acids (FFAs) depending upon the moisture content in the seed during collection as well as oil expression. In addition, several advantages of Pongamia over other food crops are higher recovery and quality of oil than other crops. As a legume, it is also able to fix its own nitrogen from the soil and atmosphere minimising the need for added fertilisers. Interestingly, Pongamia tree with characteristic seeds containing promising oils and fatty acids suitable for biodiesel production. However, keeping these value-added points, in the current study, the base line survey was under taken to assess the pongamia cultivation in the study area. The seeds were collected from the village farmers during interaction and separated the seeds from pods using a suitable decorticator. Then, the seeds were subjected for oil extraction with a specific prototype of oil expeller and characterized physico-chemically. Further, the crude oil was subjected for transesterification using methanol and NaOH as a catalyst. The reaction mixture was varied in trials with respect to variable time and temperature. Ultimately, the conversion from oil to ester was found to be significant and the yield of biodiesel from high free fatty acid Karanja oil by this approach has been observed to be 96.6-97.8 %. The optimized production was achieved about 97.8% using a 4.8:1 molar ratio of oil with methanol at 90 ºC. Later, the obtained esterified oil (biodiesel) was subjected for physicochemical characterization and compared with ASTM biodiesel standards. In conclusion, the pongamia esterified oil found to be most significant with respect to its optimized biodiesel production which can be re...