Technologies for biodiesel production from used cooking oil — A review

Transesterified vegetable oil (biodiesel) has recently attracted enormous attention all over the world as an alternative fuel for diesel engines because of its renewability. Biodiesel can be produced from renewable sources such as vegetable oil, animal fat and used cooking oil. Currently, the cost of biodiesel is high as compared to conventional diesel oil because most of the biodiesel is produced from pure vegetable oil. However, the cost of biodiesel can be reduced by using low cost feedstock such as animal fat and used cooking oil. This paper reviews the work that has already been done in technologies for biodiesel production from used cooking oil. The fuel properties of biodiesel from used cooking oil were also reviewed and compared with conventional diesel oil. In addition, biodiesel specifications provided by different countries were also presented.