cplmac Posted March 6, 2008 Posted March 6, 2008 Hello all, I've got a large quantity of Sodium Salicylate that is to acidic. I've had a batch before that was to acidic and it performed very poorly, this performs better but is still noticeably weaker than the high quality air milled salicylate I have had in the past which had a lower content of acid. My question, is there a way to decrease the level of acid in the salicylate?
Mumbles Posted March 6, 2008 Posted March 6, 2008 It's difficult to say without knowing the acid content, nor the acid make up. Assuming the acidic nature is from excess salicylic acid, one could potentially neutralize it with sodium bicarbonate. Again, a bit hard to do accurately without knowing the starting acid content. It might be possible to do in batch methods by ball milling the two together. The grinding action might be able to provide sufficient contact for neutralization in addition to any water content in the two products.
asilentbob Posted March 6, 2008 Posted March 6, 2008 I'd do it in solution going by pH... then go through the mess of drying it all out again and milling it again...
h0lx Posted March 6, 2008 Posted March 6, 2008 provided it's salicylic acid giving it the low pH, You could heat it to 210-215 and boil the acid out. altho the salicylate would melt, so you would have to re-powder it.
Mumbles Posted March 6, 2008 Posted March 6, 2008 It should be noted it's boiling point is not 211. It's 211 at 20 mmHg. you'd have to do it under a vacuum. Another problem with doing it by soln is that pH 7 doesn't mean neutral. Sodium Sali will have a naturally basic pH at full neutralization.
asilentbob Posted March 6, 2008 Posted March 6, 2008 I meant find the stated normal pH of it in solution... then get it to that pH... youd have to do some math with concentrations and such...
cplmac Posted March 7, 2008 Author Posted March 7, 2008 I think I could try ball milling it with some bicarbonate. I was thinking maybe Adding 5% bicarbonate and 10-15% Acetone and knead it all together real thorough like then let it dry and powder it up. As soon as I get the time I'll give both methods a shot.
FrankRizzo Posted March 8, 2008 Posted March 8, 2008 Excess bicarb will steal away energy later when you're burning it, causing your rockets to be even slower. I think something like ammonia solution would work. Any excess would be removed as you dry it. Lye would probably also work..the byproduct of neutralization being water. Dunno if the ammonia or lye would destroy the salicylate though.
NightHawkInLight Posted March 8, 2008 Posted March 8, 2008 Ammonia was what I was thinking also. I don't think a dilute solution would cause problems. I have used it diluted for neutralizing other chemical compounds it supposedly damages with no ill result. I believe it would take out the acid before it begins harming anything else, so with some pH testing as you go it should be fine. That is if it harms the salicylate to begin with.
asilentbob Posted March 8, 2008 Posted March 8, 2008 Note that ammonia usually has other crap in it... id say soap... but im not sure if thats what it is. Could affect other operations with it. I know that the additives make hydrazine sulfate synths more of a pain in the ass.
FrankRizzo Posted March 8, 2008 Posted March 8, 2008 So, would it be best to heat the commercial ammonia solution and bubble the gas through the salicylate solution?
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