Magnetite Removal
- 1). Precipitate magnetite by using a bar magnet. Place bar magnet under the beaker containing magnetite and leave for a few minutes. Magnetite will be drawn toward the bottom of the container.
- 2). Test solution above, which is being drained of magnetite, to see if it still has significant quantities of magnetite. Because the magnetite is moving to the bottom, the solution will appear murky brownish-black regardless of the presence of magnetite, so you will have to centrifuge (spin at very high speeds) an aliquot of it (a small amount; about 500 microliters). If the solution still has a uniform brownish color after centrifuging at 12,000 rpm for 5 minutes, then you don't have a substantial amount of magnetite in solution. If you have an unmistakable black pellet of magnetite at the bottom of the centrifuge tube after centrifuging, then you have magnetite in your solution and must continue to purify your solution of magnetite. If the latter is the case, proceed to step 3.
- 3). Hold bar magnet at the bottom of beaker and pick beaker up. Pour solution above the magnetite into a new, clean beaker. The bottom of your first beaker should be covered by a shiny layer of magnetite crystals. Place bar magnet at the bottom of the second beaker and allow magnetite crystals to gravitate toward the bottom. After a few minutes, again centrifuge a small amount of liquid in the beaker to determine if it contains a substantive amount of magnetite. If it does, repeat Steps 1 and 2.
- 4). Collect and consolidate your magnetite into a scintillation vial, a small bottle with a lid. Resuspend magnetite crystals at the bottom of each beaker in hexane using glass pipettes. Pipette hexane and magnetite into scintillation vial and leave vial open, in a fume hood, overnight. The hexane should evaporate, leaving behind dry magnetite particles.
