If it's wood, you are flat out of luck.

You can remove some oil from wood, but only that which is on the surface. get down below, and the fats find their way into the fibers and won't come out. Best bet, if its wood, is to sand the surface, and then prime it with Kilz or a zprimer, and then paint over it. If its somethig else, I would suggest scraping it up, then spraying with a detergent, letting it sit, then wiping it up. lather, repeat

Good luck!