Sciencemadness Discussion Board

purifying sulphur

Antman 762 - 4-10-2004 at 21:00

is there a method to seperate sulphur and bentonite mixtures. I have looked around but elemental sulpher doesnt seem to dissolve in anything, Ive seen mention of sublimation but need details being a newbie

unionised - 5-10-2004 at 15:01

Sulphur disolves in plenty of solvents.
http://www.speclab.com/elements/sulfur.htm
gives some examples.

BromicAcid - 5-10-2004 at 17:19

It lists sulfur as slightly soluble in water and alcohol. Nothing worth noting in my opinion. Sulfur is supposedly soluble in benzene, one of the reasons I acquired that specific solvent, however it's only soluble to the extent of 1 g / 100 ml or so. The only good solvents for sulfur that I can think of off hand are sulfur chlorides, carbon tetrachloride, and carbon disulfide. Although I am sure there are other good ones.

So it's a sulfur/bentonite mixture. What are the physical properties of the mixture? Is it homogeneous solids or powdered versions of each solid. Bentonite depending on the type may well be soluble in water. Boiling the mixture in water and skimming the sulfur off the top may well be possible. Even if the bentonite is not appreciably soluble it would be worth a shot.

Sulfur does make it to its boiling point so it's not really a true sublimation. However you could heat a steel pipe filed with the mixture (being extra sure to have a place where gas can exit and just have one area of the pipe cool or put a bend in it. The sulfur will boil off the heated side and condense in the cooler area. Wait to cool, open tube, scrape out sulfur.

Might also be good to know:

1) What are you going to use it for?
2) How pure a product are you planning on?
3) Anything else about the physical properties of the mixture (already mentioned this question).
4) And finally, what kind of heating equipment do you have that might be suited toward the disillation/sublimation of sulfur.

Anyway, just trying to help, we can better help if you help us to assess your situation.

Antman 762 - 5-10-2004 at 18:18

the bentonite sulphur mix might be homogeneous (its standard garden fertilizer found in the shed)

The reason i was planning to use the sulphur to "jack up " my priming compound in my flintlock.

Equipment available = full distillation rig could do any distillation/ sublimation required, im just not very imaginitive and have not crossed my two hobbies in this manner before.

I was going to dissolve the bentonite in water (hot water required) to see if i would be left with two seperate chemicals so we will see.

Its merely curiosity for if i cannot seperate the two sulpher is easily available here but i figured i would rise to the challenge for science is a use it or lose it knowledge.

Probally wont distill or sublimate due to toxic nature of some of the sulphur gas compounds so i think best bet is Water.

I do have a few litres of benzene so i will try that route as well and report back

S.C. Wack - 5-10-2004 at 19:29

I'm curious as to whether the bentonite would form a layer on top of molten S, or if it would suspend in it as a colloid - at a temp at which S is fluid.

Perhaps you could melt a few grams and let us know?

Antman 762 - 5-10-2004 at 20:49

will do

ldanielrosa - 31-1-2011 at 01:11

I didn't see a conclusion on this one. I have the same issue: I purchased a couple boxes of the garden sulfur (10% bentonite), and now I'm trying to clean it up.

I did a melt on it, and the results were not promising. There was a clean layer in the middle- maybe 10% of the sample with dirty stuff above and below.

Now I'm trying boiling water on it. I have the means to grind the prills into powder and sift, about 0.25mm maximum particle size. The water is turning grey and the powder is fluffing up.

Maybe I could add something to raise the boiling point of water or put it in a pressure cooker, so the sulfur would actually melt and the bentonite would be a bit more mobile?

peach - 31-1-2011 at 06:34

Well the topic is interesting (solvents for sulphur) but you may be better served not by trying to dissolve it out of those mixture but by getting a cleaner source to begin with.

You can buy sticks of clean sulphur at some pet stores. It's put in doggies water bowls during the summer to keep them cool and known as rock sulphur.





You could also try separating the sulphur using heat. It is not essential to sublimate or distil it to affect a good separation from some mixes. The sulphur will reliquefy even when in close proximity to a blowtorch flame (a turned down blow torch flame). Once it's cooled, you can pour out the contaminant and then recover the sulphur.

The following photos are to show how you can move it around in glass, it's not a bentonite mix in there. I expect it'll behave in a similar manner with bentonite.








Jor - 31-1-2011 at 09:20

Extract the sulfur with hot toluene, in wich it is quite soluble. Cooling the toluene (I think xylene will also work, or impure paint thinner containing a significant amount of these), will give beautiful sulfur crystals. Then you can re-use the solvent to extract more sulfur.