Many, but not all, aluminum alloys can be oxyfuel welded. What alloy do you want to weld? And what kind of structure are you welding?
I recommend getting a copy of "The Oxy-Acetylene Handbook" published by Union Carbide. I pretty am sure it is long out of print. My copy was printed in 1954. But it shows up on eBay frequently.
IMHO for most applications you would likely be better off using GMAW or TIG. Is there a particular reason you want to use oxyfuel?