Here’s how I do it, and many have been Bens Best tools:
Needed: hand held propane torch, uses smallish camping propane bottle that screws to the torch, strap wrench, bench vise
Place the steel far end of tool into the vice, I use leather to prevent marks. Locate the flute edges against the vice jaws so the tool wont turn. Adjust the strap wrench to fit around tthe wooden handle, hold it in place while heating the steel, close to the ferrule. I test with the strap wrench before heating, a time or 2 I didnt need heat. Just keep heating and testing with the strap wrench until the handle breaks free, and just spin it around a few times to reduce friction, while applying some side pressure with the wrench and pulling with the other hand.