What is biofuel?
Biofuels or biodiesels are fuels that are, in essence, biodegradable and non-toxic. They are manufactured from vegetable oils, waste cooking oils, animal fats or tall oil (a by-product of the pulp and paper industry). (NBEP, 2007). These oils undergo a process called transesterification whereby they are subjected to a reaction with an alcohol (usually methanol or ethanol) using a catalyst such as sodium hydroxide. The resulting chemical reaction produces an ester called biodiesel and a by-product called glycerin. (Canada, 2007)
Pure biodiesel fuel is significantly less flammable than petroleum diesel which burns at 50 degrees Celsius. Biodiesel’s flashpoint (the temperature at which it will ignite if it is exposed to a spark) is about 150 degrees Celsius. Pure biodiesel tends to lose its viscosity or to gel at lower temperatures when compared to petroleum. (Canada, 2007). This can be a concern for its use in colder climates. Biodiesels are often used in combination with petroleum diesel and are referred to as biodiesel blends. These blends will have a flashpoint and a gel point somewhere between the two pure fuels depending on the mixture.
Biodiesel can be blended with diesel in any concentration but that which is used in Canada at the present time is usually a 5% or a 20% blend. (Canada, 2007). In France, however, where biodiesels are more commonly used, even for heating fuels, blends of up to 50% are employed. France is currently the world’s largest producer of biodiesel. (Fuels, 2007).