Rogue Chemist Posted December 24, 2008 Posted December 24, 2008 I have been asked to conduct some thermite demonstrations at university.I will be using thermites of iron oxide, copper oxide, bismuth oxide, and calcium sulfate(not technically a thermite, but it is impressive), for the range of properties they display. However I want to make it classy and use electrical ignition, which for copper and bismuth oxides is as easy as a simple BP squib(christmas bulb type ignitor), however simple BP does not ignite the iron oxide or calcium sulfate based thermites. What mixture should I use that is easily ignited, yet burns hot enough to ignite these thermites? Rare chemicals are no object, but no toxic metal salts can be used.Thanks
firetech Posted December 24, 2008 Posted December 24, 2008 Many thermite compositions are lit with Mg ribbon. If you could find an ignitor for that then the ignitor could ignite the Mg ribbon then that could burn down to light the thermite. Check nakka-rocketry.net for ignitor ideas. Hope this helps.
Miech Posted December 25, 2008 Posted December 25, 2008 Plain KNO3 flash usually does the trick. 5 KNO33 Sulfur2 Aluminium Any sort of aluminium finer than approximately 200 mesh will do.
Yankie Posted December 25, 2008 Posted December 25, 2008 Well for my CuO:Al thermite I use S:Al prime, It takes a bit to get going, I normally use BP + Al to light it, but that is with 300 mesh spherical Al, With finer Al, even flash Al, it should light a lot easier. It burns, (smoulders) very hot and glows very brightly.
Richtee Posted December 25, 2008 Posted December 25, 2008 Well for my CuO:Al thermite I use S:Al prime, It takes a bit to get going, I normally use BP + Al to light it, but that is with 300 mesh spherical Al, With finer Al, even flash Al, it should light a lot easier. It burns, (smoulders) very hot and glows very brightly. Careful with that stuff. I had a pile go POW! The CuO/AL i mean.
jacob Posted December 25, 2008 Posted December 25, 2008 Careful with that stuff. I had a pile go POW! The CuO/AL i mean. On purpose or by accident?
Yankie Posted December 25, 2008 Posted December 25, 2008 Careful with that stuff. I had a pile go POW! The CuO/AL i mean.I am using 200 mesh Al so it is much less reactive, I still take lots of safety precautions.
Rogue Chemist Posted December 25, 2008 Author Posted December 25, 2008 Thanks xetap and MiechI'll give both a try in the new year.
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