If you're talking about one of those little torches that hook to a small propane cylinder that people use to solder plumbing joints with then yes you likely can do so with a propane tank hose and the proper connections.
They have torches that you can hook up to 20 lb propane tanks to set brush fires with.
So as long as you have the proper connections and the hose then it shouldn't be a problem to hook a little propane soldering torch to the propane tank.