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Author: Subject: Chromate/Dichromate thermite
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[*] posted on 5-8-2020 at 10:08

Oh I see what you mean I just saw dichromate and did not put two and two together chromium thermite uses chromium 3 oxide. The reaction I stated uses zicronium so I suppose it is a slow reaction to form ceasium in a vacuum

[Edited on 5-8-2020 by symboom]

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[*] posted on 16-9-2020 at 09:16

I did this using sodium chromate and 1/3rd of the weight of the chromate+aluminium of CaF2 as flux. When I was drying out the chromate in a beaker I put in the CaF2 since I thought that would lead to better mixing, but this led to it forming a cement-like thing that cracked the beaker when it dried and required breaking with a hammer and then grinding for quite a while in a mortar and pestle to grind up. It still had some large chunks left. When I ignited the thermite, it burnt very bright but you could still see yellow from the chromate on the surface of the slag when it cooled and there were many bubbles from escaping gases (guessing water vapor). I crushed up the slag with a hammer, then soaked it in water which dissolved a large portion of it, as the slag is mostly sodium aluminate. However, there was still maybe half of it left from the CaF2 and maybe some calcium aluminates that formed. The chromium had a lot of slag stuck on it still which was pretty much impossible to get off unless you were willing to smash up the globs of chromium metal (it is pretty brittle). Might try this again in the future with no flux at all since the sodium from the Na2CrO4 will act as one too, and this way the whole thing can dissolve in water.
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