What is biodiesel?
Biodiesel is a biofuel equivalent to petroleum diesel. It’s usually produced from vegetable oils, but vegetable oil is not biodiesel. Biodiesel is less toxic than table salt and more biodegradable than sugar. It’s not classed as a flammable liquid. The technical name for the production of biodiesel from natural oils and fats is transesterification. It’s a complicated process, but the main principles are as follows: • Vegetable oil is dried to remove any water. The quantity of free fatty acids in the oil is obtained by chemical analysis, so the correct amount of catalyst can be calculated. • Next, the oil is heated and mixed with the catalyst (strong base) dissolved in an alcohol. The oil is stirred for approximately two hours, by which time the chemical reaction should be complete. • The oil is left to separate. The waste products sink to the bottom and the raw biodiesel floats to the top. The waste products are drained off. • Finally, the biodiesel is washed to remove impurities and d
