How to Clean Tincture of Iodine Stains

Some of me very valuable document (white in color) got stained in Tincture of Iodine that i was using to clean a wound. The papers turned black and i was asking if you guys have any advice on which chemical or detergent i can use to clean this papers. Someone told me it's possible but i have since then lost contacts with him.

Thanking you in advance for your time

Abebe