Ok, I notice that a whole bunch of folks have veiwed this topic and no one has made a reply. I received an e-mail from a National Bio-deisel research/information/reference group; apparently you cannot use mineral oil for the production of Bio-deisel. You can, however, use it for brake fluid, power steering fluid, and in some cases engine oil. Refined mineral oil is basically the same thing as synthetic motor oil; it's just pretty light weight. So if anybody runs accross any of this oil, here are some usages for it.
