i tried some electrolysis on some know3. not so effective, gave a very large cloud of white smoke(?), same thing when i heated it with a torch. it might of made a little CuNO3, copper electrodes. would adding a little carbon to just leave the potassium through decomposition work, or would a better substance be potassium citrate or acetate to get the metal? potassium chloride is a little hard to do, i have no easy to make an inert atmosphere or stop the K from burning. its a pretty colour though.