plasma
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Preparation of sulfur
I belive sulfur can be made this way :
CaSO4 + 2C -> CaS + 2CO2 (heated)
CaS + 2HCl -> CaCl2 + H2S (H2S is very toxic gas)
Three ways of oxidizing hydrogensulfide :
2H2S + O2 -> 2H2O + 2S (Use charcoal dust as catalyst)
2H2S + SO2 -> 2H2O + 3S
2H2S + O2 -> 2H2O + 2S (H2S is burned in air)
I know theese reactions accur, but I don't know at which tempratures. Any comments ?
(I know sulfur can easely be obtained in stores, but unfortunantly that's not a fact in Norway)
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madscientist
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You could react the CaS with H2O2, much simpler.
8CaS + 8H2O2 --> 8Ca(OH)2 + S8
I weep at the sight of flaming acetic anhydride.
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plasma
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Thanks ! never thought of that one.
Will this reaction work with 5% H2O2.
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plasma
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CaS is a shiny transparent mineral, right ?
BTW why did you write :
8CaS + 8H2O2 -> 8Ca(OH)2 + 8S
and not just :
CaS + H2O2 -> Ca(OH)2 + S
What temperatures should be used +
Thanks
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plasma
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Correction :
CaS is not a shiny transparent mineral, it's a grey solid. CaS is also fluorescent, this means it glows in the dark.
NOTE: The temperatures needed for the reaction is rather high and it should be done in a cheramic bowl. I heated this mixture (CaSO4 & C) in a steel
vessel, after 25 minutes of heating the vessel started to melt.
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PHILOU Zrealone
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The fact CaS is fluorescent lyes in the fact the impure CdS and ZnS are in too when natural mineral is analysed! Synthetic CaS displays no
fluorescence!
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Blind Angel
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he didn't wrote:
8CaS + 8H2O2 -> 8Ca(OH)2 + 8S
he wrote (sub added):
8CaS + 8H<sub>2</sub>O<sub>2</sub> -> 8Ca(OH)<sub>2</sub> + S<sub>8</sub>
S<sub>8</sub> is OctoSulfur, i know it exist but i dont know much else sorry
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Theoretic
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H2S could be decomposed by heat at about 400C.
I don't know how you could make use of H2, though.
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blip
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Quote: |
You could react the CaS with H<sub>2</sub>O<sub>2</sub>, much simpler.
8CaS + 8H<sub>2</sub>O<sub>2</sub> --> 8Ca(OH)<sub>2</sub> + S<sub>8</sub>
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Are you sure this wouldn't produce CaSO<sub>4</sub> instead? I've seen H<sub>2</sub>O<sub>2</sub> used
to convert PbS to PbSO<sub>4</sub> to restore old paintings.
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vulture
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True, I was thinking of the same problem.
The H2O2 method will work with H2S IIRC.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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