according to wikipedia (yeah, i know):
One form of synthetic oil is that manufactured using the Fischer-Tropsch process which converts carbon dioxide, carbon monoxide, and methane into liquid hydrocarbons of various forms.
Another form of synthetic oil is that produced at Syncrude sands plant in Alberta, Canada. This huge facility removes highly viscous bitumen from oil sands mined nearby, and uses a variety of processes of hydrogenation to turn it into high-quality synthetic crude oil.
Thanks .