You can melt comb and strain it through paper towels, cloth, etc. and come out with beautiful wax.
But how do you clean up propolis?
I stopped collecting it a while back and I have started back again. I clean it off my boxes and frames. Starting to get a decent amount. When you scrape it off you get bits of wood and paint.
I was thinking about heating it up some as it becomes very soft as it gets warmer and then find a way to filter out the foreign materials. But the propolis may have to get hot enough that the paint melts too.
I have 4 propolis traps I need to put on a few of my hives that love to make propolis. Keep them busy during the dearth.