Sciencemadness Discussion Board

Making CaC2 using a DC welder

metalresearcher - 24-11-2018 at 12:45

I repeated an earlier esxperiment of making calcium carbide which succeeded.
I put some charcoal with CaO powder in a crucible and put two carbon rods attached to a 140A DC welder into it.
I let it run a few minutes, which resulted in a very bright pinkish light and after cooling, I got a few chunks of (impure) CaC2 from the crucible.
The reaction is CaO + 3C => CaC2 + CO. The carbide is formed in a liquid state at a temperature well above 2000 C which freezes when cooling.
Throwing the carbide in water results in lots of C2H2 gas.

Here a video:

https://www.metallab.net/jwplayer/video.php?v=L2NsaXBzL0VBRi...

hissingnoise - 24-11-2018 at 13:16

I thought about trying it a few times but in the end, I just ordered it off ebay ─ not as satisfying maybe, but a lot less effort...


Ubya - 25-11-2018 at 04:36

is it possible to measure the acetylene formed and from that calculate how much calcium carbide was made from the strarting reagents (just to have an idea of the yield)