The greece collected from restaurants, called yellow greece, has been recycled even before the word recycle was popular. Yellow greece goes into the manufacture of soap, makeup, clothing, rubber, detergents and gunpowder, its principal use is as a livestock feed additive to make the feed less dusty. Yellow greece is even traded on the commodities markets. The current market price for yellow grease ranges from 15.5 to 16 cents a pound which comes to well over $60 per barrel. So you can see how it is cheaper to buy crude oil over yellow oil as both will need to be refined for use as diesel.
A Recipe for Biodeisel