Physicochemical Properties of Biodiesel

Biodiesel fuel properties both physical and chemical have significant impact on combustion performance and emission characteristics of compression ignition engines and the production of NOx gases. The physicochemical properties of biodiesel except for the viscosities of ethyl esters and ethyl esters are comparable. However, the pour point and viscosity of methyl ester compared to ethyl esters differ largely. For example, methyl esters produce more torque per unit of biodiesel used compared to ethyl esters. It is also interesting to note that in biodiesel physicochemical properties, the heat value of combustion could be similar or identical but find different combustion, performance and emission characteristics behaviour. One of the critical physicochemical properties of biodiesel is viscosity especially in compression ignition engines. This chapter looks critically at the influence of biodiesel physicochemical properties and the role they play in the combustion process. Secondly, this chapter looks at the role of different influencing factors with a physicochemical property under discussion such factors which affect the kinematic viscosity of biodiesel could be interlaced with other properties yet unique to a property. Thirdly, this chapter will look at the equations related to physicochemical properties of biodiesel and their use in analysis and calculation of different biodiesel properties.

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  1. Howard College Discipline of Mechanical Engineering, University of KwaZulu-Natal, Durban, KwaZulu-Natal, South Africa Semakula Maroa & Freddie Inambao
  1. Semakula Maroa