I couldn't find any guides in Instructables on isolating/extracting Iodine from tinctures and drying it, so I decided to make one myself.
NOTE: I can't stress this enough, WEAR GLOVES AND SPARE CLOTHES OR LAB COAT, Iodine is quite a messy element now that it can stain even through gloves (wearing gloves makes it easier to clean off your skin), and removing stains is not fun. If however, you do get stained by Iodine, try cleaning it with a Hydrogen Peroxide solution.
Step 1: Getting Chemicals and Equipment Needed:
- Mason Jar or Beaker
- Coffee Filter
- Container with cap, Snapple bottles work great. I am re-using mine from a past Iodine extraction.
- Air-Tight container, either glass or tempered plastic.
- Spatula or flat stick
- Lab Coat or spare Clothes
- 60ml Iodine Tincture
- 60ml 30% Hydrochloric Acid
- 60ml 3% Hydrogen Peroxide or Sodium Hypochlorite (Bleach)
For Drying the Iodine:
- Any dessicant, I used Anhydrous Magnesium Sulfate (Epsom Salt)
- Any airtight container
- Napkin or Cheese Cloth
Step 2: Add the Iodine Tincture to the Bottle.
Pretty simple and basic. Just pour the tincture inside the bottle, its hard to mess this up.
Step 3: Add the Hydrochloric Acid
Slowly, pour in the 60ml of 30% Hydrochloric Acid and swirl the bottle to mix it well together. The mixture should have a wine-like consistency and colour.
Step 4: Add the Hydrogen Peroxide
VERY SLOWLY, add the 60ml of 3% Hydrogen Peroxide into the bottle. The consistency should turn tomato juice-like and Iodine should start to precipitate out and a purple "steam" should come off the solution. This is the Iodine sublimating. Cap the bottle and swirl it to mix the chemicals well. Let the mixture sit for about 5 minutes.
Step 5: Filter the Solution
Uncap the bottle and pour the contents into the beaker/mason jar through the filter in the funnel. You will notice that some Iodine sticks in the bottle, so use the same liquid collected in the beaker/jar to wash the bottle a couple of times. Let the solution filter off.
Step 6: Transfer the Iodine Into a Container
Do this while the Iodine is still wet, even though it is almost impossible to scrape it all off the filter, if it dries out it will start sublimating, something you dont want, mainly because it will stain your roof and walls, and it will also lower your yield. Transfer the Iodine into a small, air-tight container and prepare to dry it.
The dirty filter can be placed inside a jar and soaked in Ethanol to dissolve any Iodine left on it. Later it can be stored in aqueous form.
Step 7: Drying
Make a "pouch" of a decent amount of your dessicant chemical, I over-did it by quite a lot, about 3 grams of it should work. I suggest oven-dried Magnesium Sulfate as a dessicant now that it is cheap and easy to get. Place the pouch in the container WITHOUT IT TOUCHING THE IODINE, and screw the cap on ontop the little "tail" left of the pouch to hold it in place. Place the bottle in a cool (about 23C) cabinet or something, and leave it dry for about 24 hours.
Step 8: Final Result
The container became an orangey-violet colour due to the Iodine sublimating, and the Iodine freely fell to the bottom of the container without sticking to it. This meant the drying was done.
My gloves were stained pretty much after the extraction, and my hands were stained through them too.
I was unable to calculate the yield because my scale broke.