Experiment 37: Making Iron (III) Oxide for Thermite

In the last experiment, I made fine aluminum powder, with the intention of doing the thermite reaction.  The most common type of thermite is the iron thermite, and its second ingredient is iron oxide.  Both red and black iron oxide will work, but I used red (iron (III) oxide), because it was the most common and I saw good instructions on making it.  Basically, the process involves running electricity through iron electrodes in a brine electrolyte until one electrode is completely eroded away.  This produces rust from the iron.  I switched the polarity (+12V and ground) of my electrodes every 12 hours to even out the erosion and make the cell last longer.  After 36 hours, I drained the excess water and baked the sludge at 400°F for an hour.  I then ball milled the product to a fine powder.  I also made a video showing the system I developed of making red iron oxide in large amounts (it works quite well):