This part of the procedure will get your oily magnetite into the water solutions.
- Grind 10 grams of soap that you made into a cup which has 100 mL of water
- Boil the mixture to dissolve while vigorously stirring (takes about 20-30 minutes)
- Filter off the undissolved soap
- Take a spoonful (3-5 grams) of black waxy mixture into 40 mL of the soap-water solution
- Stir and boil the mixture for 30 minutes (add more water if significant loss of water observed)
- Filter the solution to get rid of unreacted magnetite
- Magnetically separate the nanocrystals (time varies: smaller crystals need overnight or couple days, larger ones need couple hours)
- Once on the magnet gently swirl some water on the crystals to clean them
- Redissolve in water (or ethanol, etc.)
