Sciencemadness Discussion Board

Best "cheap" way to make sulphuric Acid, or find it.

mrzwing - 14-11-2018 at 04:00

I always get a bit sad when Sulphuric Acid is mentioned, i live in Sweden and its almost impossible as a individual to buy the stuff.
no drain cleaners, and all chemical companies CAN sell to individuals but refuses. that goes for quite a lot of chemicals, nitric acid is even harder. only "strong" acid available is 30% Hydrochloric acid.

If you know of anyone in the EU who sells to individuals i would be very i would be extremely happy if you shared a link. since so far i have come up with none. it's like my ISP refuses to help me. :P

i have looked at the Electrobromine process and so far it seems like the most "cheap" and easily one.

but it there any other way to make it, and i mean any way if i so have to dig a hole in the ground to find the damn sulphur compounds myself.


[Edited on 14-11-2018 by mrzwing]

Melgar - 14-11-2018 at 05:24

It can be produced with some difficulty from magnesium sulfate (epsom salt) and oxalic acid. Dissolve magnesium sulfate in distilled water and oxalic acid in a separate quantity of distilled water. Slowly add the oxalic acid solution to the magnesium sulfate solution, with stirring. Let everything precipitate, then decant and filter. Try adding more oxalic acid solution to the filtered solution, and only stop when nothing precipitates. Otherwise, repeat. Boil the solution down to get sulfuric acid. Oxalic acid should decompose at elevated temperatures.

You can also boil down "battery acid" which is really just dilute sulfuric acid, and is needed for flooded lead acid batteries. It used to be manufactured using the lead chamber process, and so would often contain lead, but I don't think there's a single operating facility in the world that produces sulfuric acid this way anymore. The contact process is just too efficient to allow it. Still, you'd want to check for lead anyway, using commercially available test strips, since there's a chance the acid has been recycled. Considering how ubiquitous flooded lead acid batteries are in home solar and wind electrical installations, I'd expect battery acid to be available somewhere in Sweden.

mrzwing - 14-11-2018 at 06:43

Well i can get decommissioned car batteries and purify it as best i with distilling.

the Oxalic, epsom method sounds interesting might look into that. :)

Melgar - 14-11-2018 at 08:39

Don't use decommissioned car batteries. Lead poisoning is no joke.

If you have access to sodium bisulfate, you can distill sulfuric acid from that, via a disproportionation/decomposition reaction. Usually it's used to produce SO3, since by carefully controlling the temperature you can drive off water first, producing sodium pyrosulfate. That will decompose at higher temperatures to get sodium sulfate and SO3. But if you're not careful about controlling the temperature and just get it really hot (~500°C), you should be able to distill off H2SO4.

Jackson - 14-11-2018 at 08:52

I remember there was a thread here awhile ago discussing the production of sulfuric acid using calcium sulfate and sodium bisulfate/sulfate in an electrolytic cell. I will link to it if I can find it.

Ubya - 14-11-2018 at 09:00

https://www.sciencemadness.org/whisper/viewthread.php?tid=91...

this post is about making sulphuric acid from gypsum

Schleimsäure - 14-11-2018 at 14:04

Quote: Originally posted by mrzwing  
I always get a bit sad when Sulphuric Acid is mentioned, i live in Sweden and its almost impossible as a individual to buy the stuff.
no drain cleaners, and all chemical companies CAN sell to individuals but refuses. that goes for quite a lot of chemicals, nitric acid is even harder. only "strong" acid available is 30% Hydrochloric acid.

If you know of anyone in the EU who sells to individuals i would be very i would be extremely happy if you shared a link. since so far i have come up with none. it's like my ISP refuses to help me. :P

i have looked at the Electrobromine process and so far it seems like the most "cheap" and easily one.

but it there any other way to make it, and i mean any way if i so have to dig a hole in the ground to find the damn sulphur compounds myself.


[Edited on 14-11-2018 by mrzwing]


Here you can buy 5l for 47 Eur plus shipping to Sweden.(up to 10 kg fright weight 25 Eur).
http://www.aurelio-online.com/epages/61694983.sf/de_DE/?Obje...

I bought a lot of basic chemicals there years ago. His parcels are labeled with the common warning signs, in this case corrosive.

Broken Gears - 21-11-2018 at 05:01

Quote: Originally posted by mrzwing  
I always get a bit sad when Sulphuric Acid is mentioned, i live in Sweden and its almost impossible as a individual to buy the stuff.

If you ever find yourself on the other side of Øresund, we should hook up ;)

Mr. Rogers - 21-11-2018 at 07:20

It can be made from CuSO4, I'm not exactly sure how it's done... Anyone...? You would probably need high temperature.

[Edited on 21-11-2018 by Mr. Rogers]

hissingnoise - 21-11-2018 at 08:55

CuSO4 may be electrolysed at RT to plate out Cu, leaving a sol. of H2SO4 by using an inert anode!

clearly_not_atara - 21-11-2018 at 12:14

Potassium bisulfate disproportionates in the presence of ethanol to give a solution of sulfuric acid and a precipitate of K2SO4. Ethanol can then be boiled away.

j_sum1 - 21-11-2018 at 12:34

Quote: Originally posted by hissingnoise  
CuSO4 may be electrolysed at RT to plate out Cu, leaving a sol. of H2SO4 by using an inert anode!



I did this myself for quite a long while. Copper sulfate pentahydrate dissolved in water (I generally did batches of 50g in 200mL), lead sheet for an anode, copper wire cathode. Electrolysis slowly over 24 hours: current regulated such that I would "overcook" the solution by 10%. That seemed to be necessary to deal with inefficiencies and get rid of the last bit of copper. Boil down the solution and get reasonably strong sulfuric acid.

It is slow. But I found that if I ran it in small batches it was only taking 5 minutes of my time every 24 hours. I could boil down several batches at once.

Assured Fish - 21-11-2018 at 13:24

There is of coarse always the sulfurous acid + oxidizer method.
In my part of the world i can aquire very large quantities of H2O2 even up to 50% rathee easily without any questions asked.
If this is the case in sweden also then you can set up a SO2 generator using sodium meta bisulfite and an acid of some kind, HCl or KHSO4. Using bisulfate is my prefered method as you can just mix both powders together then set up an addition funnel to very slowly add water to the mixture. The resulting SO2 stream will come over pretty fast so just so be careful, SO2 is actually quite easy to generate with a generator as it rarely gives much in the way of suckback issues.
However you should still put an suck back trap in the form of an empty flask in between your H2O2 and SO2 generator.

unionised - 21-11-2018 at 13:26

Quote: Originally posted by clearly_not_atara  
Potassium bisulfate disproportionates in the presence of ethanol to give a solution of sulfuric acid and a precipitate of K2SO4. Ethanol can then be boiled away.


Are you sure?
I thought it was sodium bisulphate that did that.

clearly_not_atara - 21-11-2018 at 18:03

It was definitely potassium:

http://www.sciencemadness.org/talk/viewthread.php?tid=79548

I'm not sure if this method depends on the lattice energy of K2SO4, but I had wondered if it might be as effective with ammonium bisulfate, which has the particular advantage that the reaction:

(NH4)2SO4 >> NH4HSO4 + NH3 (g)

happens at achievable temperatures, so the "waste" can be turned into more ammonium bisulfate, yielding ammonia as a by-product, ultimately this allows us to "split" the salt through thermochemical cycling.

RogueRose - 21-11-2018 at 18:35

Quote: Originally posted by hissingnoise  
CuSO4 may be electrolysed at RT to plate out Cu, leaving a sol. of H2SO4 by using an inert anode!



Yes I believe that is the method for production from CuSO4.

Another route you might want to consider is FeSO4 as it can usually be found at agriculture feed stores as either a soil additive or feed nutrient. It works similarly to sodium bisulfate in that it decomposes but the iron gives off SO2 and SO3 leaving Fe2O3.

The problem with any of the decomp methods is that it requires high temps. FeSO4 decomposes around 1260F and sodium bisulfate will come over around 860 IIRC.

You could use an old propane tank as the crucible, one of the 1lb tanks. Drill the mouth/hole out so you can fill it with the sulfate and then attach a fitting to it and I would suggest a good length of copper tube to drop the temp a good bit before you bubble it into the water.

macckone - 22-11-2018 at 06:46

There are also the chamber method and the vanadium catalytic method. If you can get sulfur powder, these may be cheaper.