usapyro Posted June 7, 2011 Posted June 7, 2011 How exactly do the sulfuric acid impurities get into sulfur? Do they get in there because of the industrial sulfur waste process which creates most of the retail sulfur?I was playing around with H2SO4 and some chlorate/sugar 60/40 the other day... Woah... It does not take more than 1/8th of a droplet to set that stuff off... Went off to double check my chlorate vs sulfur(kno3/kclo4, etc) mixing equipment was labeled properly... The reaction from a full droplet is faster than human reaction time... Quite impressive... I wonder if they ever used this to light the time fuse on grenades and stuff in WW2?
jimbo Posted June 7, 2011 Posted June 7, 2011 yeah maybe,the hawkins grenade had an acid ignition system when a tank ran it over it crushed a vial of acid which ignited the ignition train.
Ralph Posted June 7, 2011 Posted June 7, 2011 when sulfur is oxidised to SO2 allitlle SO3 is formed by an equilibrium with oxygen which remains fairly strongly to the left (the SO2) when SO3 reacts with water it becomes H2SO4 (aka sulfuric acid) this is how sulfuric acid ends up in sulfur you say "but Ralph we have sulfur not sulfur dioxide how dose the sulfur dioxide get there" well im glad you asked, sulfur is offten distilled at high temperatures at these temperatures and any residual oxygen may oxidise it also some say that the oxygen in chlorate can very slowly oxidise the sulfur either way thats how it happens. also worth noting that sulfur dioxide also forms an acid when it reacts with water in the air which should also be able to cause a chlorate mixture to ignite
Mumbles Posted June 7, 2011 Posted June 7, 2011 I don't know about you guys down under, but most of the sulfur used in the US is no longer distilled. Rather sublimed, which is what they really do. Also, there is little to no equilibrium with SO2 and SO3. If you have SO3, it doesn't spontaneously decompose to SO2 and oxygen, which would happen in the event of an equilibrium as you've described. The SO3 is produced along side with SO2, no equilibrium required, though one can catalyze the oxidation of SO2 with air to SO3 with vanadium pentoxide. See the contact process. Alternatively, Sulfurous acid (SO2 dissolved in water) can be readily converted to sulfuric acid by many means, and is probably strong enough as is. In any case, the chemical found to be responsible for spontaneous ignitions was Chlorine dioxide anyway, which is formed without the presence of acid directly. Sulfur Dioxide is able to reduce the chlorate ion into chlorine dioxide, but I am sure water helps at least.
50AE Posted June 7, 2011 Posted June 7, 2011 I remember reading somewhere that the exposure of a chlorate/sulfur mix to SO2 gas has made it ignite.
Mumbles Posted June 7, 2011 Posted June 7, 2011 I thought it was ClO2 that made it go up instantly. I should probably find that reference and check. The SO2 can certainly make ClO2 at least. Perhaps it was SO2 as the root cause, but ClO2 as the acting agent that lit it up by reacting with organics and the like.
Recommended Posts