Fuelstock for Biodiesel Production
A variety of oils and fats can be used to make biodiesel. Any vegetable oil or animal fat including waste vegetable oil (WVO) can easily be converted to biodiesel by reaction with an alcohol, typically methanol, and a catalyst.
Virgin oil, as the name implies, as opposed to waste oil has never been used before and is the easiest fuelstock to use but is more expensive that WVO.
Waste vegetable oil requires that you add additional basic catalysts or "pre-treat" the WVO by a process to remove any particulate matter and remove any oil that has undergone decompositon due to the high heat conditions used for frying in oil.