Sciencemadness Discussion Board

SO2 from CuSO4, S, H2SO4 and/or FeSO4?

Draeger - 4-7-2020 at 06:39

So, I wanted to do some small scale reactions with SO2, but obviously I don't have a cylinder of it standing around ready to go, as much as I'd like to have one.

Burning Sulfur isn't really an option since the reaction apparatus should be a closed system and I only have polystyrene test tubes and fitting latex tubing as a safe way to generate then transport gas which I doubt would stand any sort of flame.

Sodium sulfite/meta-/bisulfite is also apparently 30€ per kilogram and 12€ per 100 grams, not really something I'd call cheap, so I'm looking for a reaction with something I already have.

Does anyone have an idea?

[Edited on 4-7-2020 by Draeger]

Syn the Sizer - 4-7-2020 at 06:50

Have you checked a wine/beer home brewing shop? Metabisulfite is used in wine making. In Canada I got 150g for 2.99CDN + 11% tax from Harvest Brewing. If not check a wine making website instead of a reagent website, you could probably get it cheap from there.

hask123 - 12-8-2020 at 19:12

You can synthesize SO2 by heating copper in sulfuric acid, though you do need conc. sulfuric acid for this to work.

Cu + 2 H2SO4 -> CuSO4 + 2 H2O + SO2

[Edited on 13-8-2020 by hask123]

RogueRose - 12-8-2020 at 22:52

what about decomp of ammonium sulfate, if you can deal with the ammonia released somehow you are left with just SO2 IIRC.

woelen - 12-8-2020 at 23:13

Decomposition of ammonium sulfate does not give SO2. It has sulfur in oxidation state +6 and this is not easily reduced to the +4 oxidation state.

Indeed, try a shop for making wine and beer. Where I live, we have sodium metabisulfite and potassium metabisulfite in bags of 100 grams for a few euros, available in local shops. The brand of this is "Campden". Something like this should also be available in Germany:

https://www.brouwland.com/nl/onze-producten/wijnbereiding/st...

Arcaeca - 13-8-2020 at 03:33

Can you not get your hands on sodium metabisulfite stump killer? Here in the States you can get Bonide brand stump killer that's ~98% pure sodium metabisulfite, and it costs about $9 for a 1 lb jug at Ace Hardware, which... $9/lbm * 1 lbm/0.453592 kg * 0.84 €/$ = 16.67 €/kg. And Home Depot has it for $7.32, which takes it down to 13.56 €/kg. Which doesn't strike me as all that expensive.

AFAIK Germany has neither Ace nor HD, but surely whatever hardware stores you have over there will have it for cheaper than 30 €/kg. Unless you've already checked; I guess I was assuming 30 €/kg was an inflated price from a chemical supplier (e.g. Sigma Aldrich) or something.