Iodine can be purified by sublimation. Iodine sublimes meaning that it passes from the solid to gas phase without ever liquifying. Read below link for more information on how to setup a coldfinger apparatus.
https://www.thevespiary.org/rhodium/Rhodium/chemistry/povidone.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/povidone.html)