hello,
can anybody please tell me how to purfy sulphur? anything would be of great help thanks.
master of the atom
iron raven

You can't have read the rules and still posted this......

What are you trying to purify sulfur from ? You've given no indication of what you're after, you haven't even told us what source the sulfur is coming from. I can't even think of why you'd but sulfur that needed to be purified when it is so easily availiable pure, or close enough.

It's like you want to be banned.

If you really want to know, you've gone the wrong way about finding out.

Ok, here's what I know: Sulfur bought as sulfur (or sulphur) sometimes also "flowers of sulphur" in america I hear, is pure sulfur.

If you buy it from a garden centre this is most likely, I have never had any problems with mine. If you think it may be contaminated with something, then I suppose you could wash it, like over a filter, as it isn't at all soluble. That way, any soluble compounds will wash out, leaving the pure sulfur.

You also need to shorten your signature.

Theres nothing wrong the question and its not the guys first post. Let the moderators sort out whats right and wrong.

Very pure sulfur is essential in good quality black powder. Its importance in terms of quality is second only to that of charcoal. Sure you can make workable BP with shit sulfur and crap charcoal, but if you want really fast BP they are essential. Strangely, slightly impure KNO3 tends to have the least effect of the three components.

I think I can remember seeing that one of the main impurities in garden center (fungicide) sulphur was calcium carbonate (chalk). I think that it was only between 1-2 percent though, but I can't remember where, I sawn it. This could be removed by washing the sulphur with acidic water, which will react with the carbonate and turn it into a water soluble salt, this can then be removed by further washing with distilled water.

I have used this type of sulphur for BP without any problem.

well most none pyro-grade sulfurs tend to be rather acidic which in certain mixes is quite undesirable as it can prematurely cause ignition/combustion and damage to property and body parts you'd rather keep ensues.
so i think he wanted to know how he could neutralise any acid in the sulfur he bought

on a side note @ iron raven there is a typo and a misquote in one of your many signature lines. it is " cry havoc and let slip the dogs of war"

that reminds me, iron raven, your sig is 5 lines long. it must be 3 or less otherwise it'll be changed for you.

hello,
i am sorry for the really carp post. My sulphur is garding grade 80% pure. i bought it as a fungcide and has no label of ingerdiants. I can't find pure sulphur so it is the only choice i have is to purify. could it be disloved in alchol and the impurites filtered out? thanks to any one who will help
master of the atom
iron raven

I've used garden sulfur before, except mine was 90% pure and very fine (350mash size). I didn't notice much diference in the way it performed when compared to flowers of sulfur, which I believe is the pure stuff. The only major difference that I saw was that it wasn't nearly as acidic as "flowers of sulfur" and because of that it didn't self-ignite when mixed with chlorinating compounds, it needed some glycerine/antifreeze/piss or something acidic to get it going.

Your in Australia. Go to bunnings or another hardwear store and by Elemental S..Its sold as an ph thing in plants. I read the lable, 99.9% Sulphur.

500g for $8

Ha static I can do better than that (just mucking with ya dude) Go to a sprinkler/horse supply/agricultural place. I got 2kg of flour fine sulfur for $2.50!!! It's really good stuff. They also sold 5L of gylcerine fro $60 ;) and 1kg of acorbic acid for $40

iron raven, as somebody has suggested it can be purified by adding it to dilute H2SO4 and filtering it out. the H2SO4 will dissolve any CaCO3 impurities. if you lived up to your claims of being master of the atom then you would have already known that :rolleyes:

On the contrary, as Skean Dhu said, if it's rather acidic then wash with slightly basic water, with sodium bicarbonat for example.
Also look for solubility in different solvents, as acetone, it may help removing another impurities non water soluble.

and plz don't sign your message twice, it's pretty boring (and very pretentious) [let's flame them all and let the mods sort 'em out ;)]

Industrially sulfur is purifyed by destillation in absence of oxygene, good luck with this in a kitchen.. :p

arthis, if CaCO3 is the MAIN impurity then it'll be removed with H2SO4. if the main impurity only constitutes 2-3% then any other impurity is likely to be less than 1% and thus negligible.
the mixes which are sensitive to acidity are the chlorate and sulphur combinations, in which case these mixes not recomended anyway. a wash with H2SO4 and then with sodium bicarbonate solution would be only necessary if the S was to be emplyed in a chlorate composition.

we can go on about purification forever creating many elaborate techniques but until we know what its going to be used for we cannot give a right answer.

If the main impurity in your sulfur is CaCO3, then maybe HCl would be better to get rid of it. Place the contaminated sulfur in water. Add HCl making sure you keep with the molar ratios. CaCl2 is formed and redissolved in the water. S8 being insoluble in water can be collected by the appropriate method of filtration. Discard the filtrate or you could boil it down and collect the CaCl2 for use as a dessicant :D.

CaCO3 + 2HCl -> CaCl2 + H2O + CO2

yer, i'm a dumbass. HCl would of course be better. CaSO4 is quite insoluble. and H2SO4 a bitch to evapourate. HCl will evapourate as the product dries.

I've bought agricultural sulfur with bentonite clay in it, so if you don't know what's in yours, it may be that. Mine was 90% sulfur, so I didn't bother purifying it, and I haven't thought about it until now.

I have some Sunniland sulfur that is labeled as 90% pure, and has a grey color, sugesting the other 90% could be clay as well. The lack of a yellow color, even upon melting, bothers me somewhat. I've heard that it can be purified simply by melting, rather than distilling, as many impurities will settle out. I haven't had too much success with this method, although it was perfomed on a very smale scale and the viscosity may have prevented this from happening immediately.

I have some 90% + sulfur I bought from the hardware store and was wondering about this. When I researched the properties of sulfur I found that is was supposed to be flamable. But when I tried to light it with a match the sulfur didn't ignite. Maybe I will try purifying it with HCl. :)

IME the sulfur doesn't burn until it has melted at least in a small spot on the pile of powder. First it melts some then begins to burn. A stick match will do it but you need to apply it in a way that the sulfur is visibly being melted. All the sulfur I've ever had has been yellow. That grey kind would probably burn once the sulfur melted but clay would raise hell with probably most reactions. Seems like throwing dirt in the fire always screws it up.

I would try to dissolve sulphur in CS2 filter the impurity and evaporate solvent. Be careful CS2 is very flammable. Other way is sublimation in inert atmosfere maybe nitrogen...suphur suposedly is inert to nitrogen but I remember that there are some SxNy molecules but I never researched how are they made. Happy work.

To my knowledge the largest impurity in gardening sulfur is clay. There may be some CaCO3, but that's not something I would be horribly worried about, there is enough in charcoal as is. I don't think a few extra percent CaCO3 would horribly mess anything up.

There are a few possibilities. One is sublimation. This carries with it the unwanted side effect of acidic sulfur, and you'd lose a fair bit. Washing in bicarbonate solution for a few days would probably do it some good. I'm sure most know the general process of sublimation, so I won't go into any details. Doing it in open air will produce SO2, but soon the Sulfur vapor will use up or displace the oxygen and it will go fine. Distilling may be an option based on this property if you are willing to lose some sulfur. If you have a closed system the oxygen would get used up. You could try to displace the air with some inert gas like mentioned.

Another possibility is trying to dissolve the clay with concentrated acid. I've had some clays damaged by HCl, so this is a possibility, but I've never tried any known specific clays, but I think benonite would be pretty resistant.

Another thing I've heard of seems pretty simple. You finely powder the agricultural sulfur and add it to water. One of the particles floats to the top and another will sink. I hear it takes a few days to reach equilibrium, but it could be possible. I believe it is the sulfur that floats. Cold water is best.

I think the best option would be to get some Carbon Disulfide and try out a small batch. See exactly how much impurity there is. Then you can work directly with the impurity to see what will dissolve it or what not.

Or you could turn the S into something else, then turn it back into S. If you boil S with a hydroxide solution you get a solution of polysulfide and thiosulfate. After decanting from the insolubles, HCl precipitates S. It is very fine and takes awhile to precipitate. Then the baking soda treatment, obviously. Ca(OH)2 should work fine, if whatever impurities you have are insoluble.

kurtz and Mumble made few good sugestions...and made me ask myself...what purpose you had in mind for that sulphur iron raven? Beware of type of sulphur needed for what you had in mind. Mumble mentioned acidic sulphur (if BP is your goal you don't want that), and excelent procedure kurtz mentioned will give very finely powdered sulphur that you should handle with respect.

I understand that sulphur is not soluble in water, but why does it not seperate from BP when being processed :confused:

to draco aster : kurtz already answered that in a way and it is not that much water in BP processing IIRC.

I was looking at the local Elevator(grain, pet-food, horses, and fert's) and I finally found some sulphur. Only problem is it said it was 50% and it was all a liquid that you add three to four tablespoons to a gallon of water to treat plants. Nothing on the bottle about what else was in it. 500ml for $13. US. Any idea if it's worth it? Probably filter, and wash with HCl, but I think I will try to find a better place.

On the other hand I did find 5 gals of Glycerine for 3.99. Wasn't such a bad stop.

Silentnite,

Firefox has it for $2.50 a pound and say it's 99+% pure with low acid content.
http://www.firefox-fx.com/ChemQ-S.htm

Skylighter has it, too, but it's a bit more expensive and they have a 5 lb. minimum on sulphur. (some of their other chems, too).

If you buy it online, though, stock up on everything they have that interests you as the shipping rates can make it not really worth it in the long run if all you need is a pound of this or that.

5 gals of Glycerine for 3.99


No way! The cheapest I've ever seen glycerine (pure, anhydrous) is $40/gallon. You must have misplaced the decimal or you bought some glycerinated water.

I've seen 99.8+% glycerine for less than $20 a gallon. This is pure and anhydrous enough for me. If I really need to get it anhydrous for one reason or another I can just heat it and drive off that last fraction of a percent. I've gotten a smaller amount of this and it has never done me wrong. I think if you get a 55 gallon drum it is around $9 a gallon, but still no where near this outrageous price posted. To get 5 gallons for $3.99, he had better have a tanker of glycerine in the driveway.

FYI

For those of you who enjoy being able to buy small amounts of chemicals from our friends at FireFox, Skylighter, DiscountPyro, etc., you will definitely want to read about the injunction being served to FireFox by the CPSC. This is a SERIOUS threat to the amateaur pyor hobbiest.

http://www.firefox-fx.com/CPSC.htm
http://www.skylighter.com/skylighter_info_pages/article.asp?Item=72

*sigh*. Hi, my name is Illiterate Bob! I dont know how to read. Because that 5gal Glycerine I thought I saw, was actually 1 gal. :confused: Not to mention the place was charging 27.99. :eek: The .99 was faded off that bottle, I went back and double checked cause your right that did sound fishy. Picked up the bottle and did an intense study this time. Sometimes Im so absentminded I even scare myself.

My apologies. :(

EDIT: But, it was actually 99.7% pure Glycerine. That part at least was correct.

That is a lot more reasonable. If it was actually true, I definatly would have needed the address of this store. :p


Anyway about your sulfur. It won't work. It is very much bogged down with shit. I hear the sulfur itself is very fine though. It has clay, calcium carbonate/hydroxide, a few other flow modifiers, some materials designed to keep the sulfur in colloid form. You will have quite a time extracting it. See if they have "wettable sulfur" It still isn't great on the purity, but much easier to purify. A few washings with acid, and a few washings with water and you will have something suitable for pyrotechnics. It won't be the best, but it will suffice.

Or you could turn the S into something else, then turn it back into S. If you boil S with a hydroxide solution you get a solution of polysulfide and thiosulfate. After decanting from the insolubles, HCl precipitates S. It is very fine and takes awhile to precipitate. Then the baking soda treatment, obviously. Ca(OH)2 should work fine, if whatever impurities you have are insoluble.

What ratio of sulphur to sodium or potassium hydroxide?

Or you could turn the S into something else, then turn it back into S. If you boil S with a hydroxide solution you get a solution of polysulfide and thiosulfate. After decanting from the insolubles, HCl precipitates S. It is very fine and takes awhile to precipitate. Then the baking soda treatment, obviously. Ca(OH)2 should work fine, if whatever impurities you have are insoluble.

What ratio of sulphur to sodium or potassium hydroxide?

as a practical matter, for production of the highest yield of precipitated S, i've really no idea.

my first thought would be - as little alkali as is necessary to dissolve it. the higher the sulfide, the less H2S and the more S should be formed on acidification. this seems sensible, but i haven't done any quantitative experimentation with this, and don't know if this would actually be a higher yielding route than air oxidation of the sulfide/thiosulfate to thiosulfate/sulfate with precipitation of S, followed by acidification of the thiosulfate. on the other hand, little H2S will be produced if the sulfide is allowed to be well-oxidized.

there seems to be less potential for losses using the minimum amount of hydroxide and acidifying this right away. one should probably have a good scrubber for the H2S/SO2 handy.

i have here a ref saying that toluene saturated with S @ 83.5 C is 11.64% S by weight, but i wonder if there is any toluene of crystallization on evaporation, or if this is even a problem. that ref probably didn't use an agricultural S product, and the solubility of S in solvents is supposed to be dependent on its form.

a book referred me to a JACS article, which led to 4 more, all from the ACS website, and published between 1905 and 1924. none of them are practical for this purpose and so are not worth attaching, they are just convenient for illustration:
http://rapidshare.de/files/2987310/SplusOH.zip.html

as a practical matter, for production of the highest yield of precipitated S, i've really no idea.

my first thought would be - as little alkali as is necessary to dissolve it. the higher the sulfide, the less H2S and the more S should be formed on acidification. this seems sensible, but i haven't done any quantitative experimentation with this, and don't know if this would actually be a higher yielding route than air oxidation of the sulfide/thiosulfate to thiosulfate/sulfate with precipitation of S, followed by acidification of the thiosulfate. on the other hand, little H2S will be produced if the sulfide is allowed to be well-oxidized.

there seems to be less potential for losses using the minimum amount of hydroxide and acidifying this right away. one should probably have a good scrubber for the H2S/SO2 handy.

i have here a ref saying that toluene saturated with S @ 83.5 C is 11.64% S by weight, but i wonder if there is any toluene of crystallization on evaporation, or if this is even a problem. that ref probably didn't use an agricultural S product, and the solubility of S in solvents is supposed to be dependent on its form.

a book referred me to a JACS article, which led to 4 more, all from the ACS website, and published between 1905 and 1924. none of them are practical for this purpose and so are not worth attaching, they are just convenient for illustration:
http://rapidshare.de/files/2987310/SplusOH.zip.html

I called around and luckily for me, theres a sulfur mine in town :) . They quoted me at 30lbs for 15USD and its fairly pure.

I called around and luckily for me, theres a sulfur mine in town :) . They quoted me at 30lbs for 15USD and its fairly pure.

I found this (http://woelen.scheikunde.net/science/chem/exps/S+toluene/index.html)
This person uses toluene to recrystallize the sulfur!

Xylene works even better, dissolving twice as much sulfur as toluene does.