Maui3 - 20-10-2024 at 02:23
I’ve had a tough time sourcing sulfuric acid in the EU, so I’ve compiled a few methods (i found helpful) to making it yourself..
Also I just briefly mentioned each method, since I want this to be more a way for everyone wanting sulfuric acid to see some more ways to do it - as
the amounts and reactions you can find yourself.
The methods are listed from (what I think was) the worst to the best method ..
1. CONCENTRATION OF ACID:
Even though the most popular way of concentrating the sulfuric acid is by distilling it, you can just concentrate it by boiling off water instead,
since sulfuric acid has a very high boiling point. Of course, this cannot be done to obtain very pure sulfuric acid, if you have a lot of non-volatile
impurities. But most of the time, this should be fine for amatuer chemistry uses. You can test if its concentrated enough, by taking a glass rod,
dipping it in the hot sulfuric acid and dripping a small amount on some toilet paper. The toilet paper should go black. PLEASE WEAR SAFETY EQUIPMENT,
IT WILL DO THE SAME TO YOUR SKIN AS TO THE PAPER.
1.5. CONCENTRATION OF ACID BY DISTILLATION:
You can also get purer sulfuric acid by distilling it at sulfuric acids boiling point, which is 337 C. Please just boil it down instead. You do NOT
want to get boiling sulfuric acid on you.
2. SULFATE SALT + ACID METHOD:
A sulfate salt like Ammoniumsulfate or Coppersulfate, which can be bought in hardware stores, is mixed with Oxalic Acid in aqueus solution. It is
important that this is a acid, that'll make a salt with the ammonia or copper in the case of ammoniumsulfate and coppersulfate that is NOT soluble in
water. That way it can just be filtered off. The mixture is concentrated by boiling down the solution (see method 1).
3. SULFATE SALT ELECTROLYSIS - MY VERSION (my favorite):
Another simple way is to electrolyse a sulfate salt like coppersulfate. This method has by far worked the best for me. You can simply use the graphite
in pencils as the cathode, and anode. Copper will not work, since it'll react with the acid making coppersulfate. In my experience even the graphite
pencil rods got a bit corroded. I stacked (and taped) some batteries together, with the negative and positive terminals of the battery being connected
with copper wire to the anode and cathode. Electrolyse, and filter off the copper through a filterpaper (possibly also cotton). If it's still blue you
can remove the last part by adding some oxalic acid to precipetate copper oxolate, which can then be filtered off, as it is insoluble in the mixture.
I got a decent conc. amount from this. And now just boil down the solution to concentrate (see method 1). Would DEFINETLY reccomend.
3. CAR BATTERY
If you have too much money you want to spend on a car battery, or you just have one laying around, you can just get the sulfuric acid out of it, and
boil it down to concentrate it (see method 1).
4. DRAIN CLEANER
If you can find some drain cleaner that consists of conc. sulfuric acid, you can just use as is, or distill it to concentrate if you need really pure
sulfuric acid. (see method 1.5). If the drain-cleaner is mixed with water you can just boil it down to concentrate it (see method 1).
5. JUST BUY & CONCENTRATE
The best method is just to buy some 12% sulfuric acid and boil it down to concentrate it (see method 1). It is far cheaper, far more efficient, and
far quicker to do. You also do not need to distill it. You can get the 12% sulfuric acid in the EU pretty easily. I don't really want to name one of
the places you can get it, in case they get flooded with people buying sulfuric acid, and they take it down from the shop, though that is not likely
to happen. But you should be able to find at least one place selling it if you have more than 1 braincell.
6. ALTERNATIVES
There are a lot of alternatives to sulfuric acid, which are not regulated in the EU. Though, as far as I know, there is not ONE alternative for every
property of sulfuric acid, you can use f.x. Sodium Bisulfate or Methanesulfonic acid for Fischer Esterification, and more.
7. LAST NOTES
I am not a native speaker, and I might have said or spelled a few things incorrectly. I am sorry for that. Also please be careful with this. Sulfuric
Acid is really corrosive. I do not take responsibility for what will happen if you follow this information. Please be careful.
Please everyone, if you have some other methods please share! I would love to make this a sulfuric acid thread.
Maui3 - 20-10-2024 at 02:24
The Concentration of acids do not count as worst method - should have said that.
Mateo_swe - 7-11-2024 at 05:40
The solution to all your sourcing difficulties is to talk to some of the people in the Reagents and Apparatus Acquisition section.
j_sum1 - 7-11-2024 at 14:40
Lead is a good anode for electrolysis methods.
It builds up a nice coating of PbO2. Bonus, you end up with a pretty functional PbO2 electrode.
I have had best results by keeping the current density low and being patient. If you need more product it is better to scale up than to push the
current high.
My experience is with using copper sulfate. You will need a membrane if you are using magnesium sulfate. However, Epsom salts, a few wall warts, a
flower pot, a bucket and some scrap lead is likely to be the cheapest possible setup.