Making H2SO4

[zoteman94]

This can sound ridiculous, but I can't buy any sulfuric acid... So I want to make mine.

I noticed that 2HCl+CaSO4=CaCl2+H2SO4 is indeed exothemic, but I saw somewhere that CaSO4 doesn't dissolve in HCl.

Do I have a problem with entropy here? (so just heating it will work), CaSO4 is indeed soluble or maybe the levels of hydration affects something?

[hypervalent_iodine]

CaSO₄ is not soluble in water or in HCl. Heating it won't do anything.

[mississippichem]

You would be better suited with a soluble bisulphate or sulfate like sodium sulfate and acid. Do you really need sulfuric acid though? The process will not be pretty.

[DrRocket]

This can sound ridiculous, but I can't buy any sulfuric acid... So I want to make mine.

I noticed that 2HCl+CaSO4=CaCl2+H2SO4 is indeed exothemic, but I saw somewhere that CaSO4 doesn't dissolve in HCl.

Do I have a problem with entropy here? (so just heating it will work), CaSO4 is indeed soluble or maybe the levels of hydration affects something?

 

How hard can it be to buy sulfuric acid? It is rather common and readily available.

 

 

http://www.dudadiesel.com/search.php?query=sulfuric&affiliate_pro_tracking_id=17:25:

[zoteman94]

How hard can it be to buy sulfuric acid? It is rather common and readily available.

 

 

http://www.dudadiese...acking_id=17:25:

 

 

Because I live in Costa Rica, and don't go out home very often... only for going to high school and the Church... And buying chemicals from other countries is problematic for me... But I think I'll just go to a battery store ASAP... (they aren't very near to my home)

[ajkoer]

A recipe that I have not tried so I cannot state that you will make something useful is as follows:

 

1. Prepare fresh HClO. One way to prepare is by adding vinegar to bleach (NaClO). Boil this dilute solution of HClO (and sodium acetate) and capture vapor and gas (HClO and Cl2O, the gaseous anhydride of HClO) in distilled water. Only boil off half of the solution as this will capture 5/6 of the total available HClO in solution. Note, with time concentrated HClO disproportionates into HCl and HClO3, and also on heating at 70 C or higher.

 

2. Gentle heat Sulfur in HClO (even dilute HClO should work per Watt's Dictionary of Chemistry Vol 2). This will make H2SO4 and HCl. You should be able to buy sulfur in a plant and garden store as "Flowers of Sulfur", which should be washed in distilled water prior to use to remove any organic wetting agents.

 

If solution is too dilute for your purpose, carefully distill to concentrate.

 

Note, substituting phosphorous for sulfur, per Watt's, makes phosphoric acid. Using Iodine makes Iodic acid, etc., as HClO is a powerful oxidizer.

 

Good luck.

[zoteman94]

Hmmm, interesting method, but Cl2O and gaseous HClO aren't "a bit" dangerous?, I also don't have any sulfur. Maybe I'll try that later, just for experimenting, but for now, the best is by logic... to buy it from a battery store and my lab teacher said that there's a hardware store that sell it near his home, so he maybe can get me some. Thank you for helping.