Making H2SO4 from HNO3

[blindreeper]

I don't know if this is in the right forum but here goes. I can't get small amounts of H2SO4 or HNO3, but I can get 15L of 90%> nitric acid for $115 :D . Is there anyway to make conc. sulfuric acid out of the nitric acid? I was thinking something like this :

HNO3 + MgSO4 ---> H2SO4 + Mg(NO3)2

Would this work? I read about using a nitrate along side sulfuric acid in nitrations, can I use a sulfate along side nitric acid to nitrate things? Mainly I want to make nitrostarch, nitrocellulose and other nitro synths. If i were to nitrate cellulose with HNO3 and MgSO4 would I make the nitrating mixture by dissolving as much MgSO4 into the HNO3 as possible?

[Mr Cool]

Oh god, NO!!! Don't use >90% HNO3 for nitrocellulose!! Make RDX!! Then you won't have to make H2SO4!!

You could also use acid of that strength for many nitrations such as NC. If you add a dehydrating agent, for example ANHYDROUS MgSO4, then it will help, but it won't be as effective as a mixture with H2SO4.
You can't distil H2SO4 from HNO3 and a metal sulphate because of the boiling points of the two acids, and H2SO4 + Mg(NO3)2 --> MgSO4 + 2 HNO3 is favoured over 2 HNO3 + MgSO4 --> H2SO4 + Mg(NO3)2, because H2SO4 is the stronger acid and holds it's H's less strongly than HNO3.

But please, don't waste it :) . Make RDX or PETN.

[Marvin]

You should be able to find sulphuric if you look long enough, either acid for car batteries, which you boil down, or some of the more expensive brands of draincleaner. Its an interesting thought experiment though, assuming something so hard to get as nitric is freely available and you have to make everything else out of it.

If you can get sulphur, and most people can if they try hard enough, burning it and leading the fumes into the nitric will eventually give you mostly sulphuric, which you will have to boil to get rid of the remaining nitric and water formed. If this is too complicated, simply adding solid sulphur to the nitric will eventually react to give a similar mixture to above, but with less sulphuric, more nitric, and a lot more water.

Both these should be done outside as they will produce a lot of very toxic NOx gasses.

[blindreeper]

Ok thanks for the help. But I have no phenol for PETN, but I do have every thing else listed for it, acetone, nitric acid (next week :D ), sodium carbonate and water (this was so damn hard to find) Hmmm, RDX sounds like a good choice, I got a cheap source of formaldahyde and ammonia. I would rather make the hexamine opposed to buying it cause if i'm gonna make something like RDX you want to chems to be pure as possible. And doesn't RDX require fumming nitric acid? In Oz sulfuric is hard to come by, I found it for 98% 500mL for $21 AU. Batteries are expensive. Does any one know how much sulfuric acid you can get out of a standard car battery. Would the old 'dead' batteries from a car yard have the sulfuric acid still useful in it, cause I got a friend who's dad just collects old car batteries and have about 50 of em he said I could have. If I did boil the sulfuric down would a plain old borosilicate beaker and a bunsen burner do it?

[kingspaz]

you don't need phenol for PETN!!! do a search!
yes a beaker and burner will do for boiling down battery acid. i used to get my acid from car batteries. you get aroun 4-5L of 20-30% H2SO4 (actualy conentration depends how fucked the battery is). coincidently i used to get my batteries from the scrap yard too. i'd just drive in, load up my car and drive off then bring them back empty the next day :) . the best way to do it is charge the battery up (raises the H2SO4 concentration to the highest it will go) then take it off charge and remove the lid sealing the cells ('sealed' cell lids can easily be removed with a screw driver). next tip it over wuickly inside a bucket to collect the acid and watch to not get any on you. then pass it through a filter to remove bits of lead and other crap in there. then you should have a nice clear H2SO4 solution. put it in the beaker and boil off the water. it must be boiled until thick white fumes come off it (H2SO4 vapour - don't breathe it as it'll burn your lungs out).

by the way greater than 90% HNO3 is fine for RDX. you won't get the best yield but you won't get the worst either. before you do anything do some fucking research!!! it is quite evident from your post that you don't really have much of a clue. don't just blindly follow instructions have some idea why you are carrying out a particular step.

[blindreeper]

What type of bucket can I collect the acid in? Not metal cause it will eat it, but will it affect plastic buckets? What type of filter do you use. I only got a small filter funnel (90mm) and normal filter paper. Flappa tells me he uses a t-shirt over a bucket and pours his AP in it, he reckons it works fine. So can I use a t-shirt (don't think so) to filter the lead crap from the sulfuric. Or is the concentration of the sulfuric low enogh not to afect the bucket or t-shirt?

[CyclonitePyro]

That seems funny to need to make sulfuric acid from nitric acid. Shows how we all have different hard to get and easy to get supplies.
Here we have a store called NAPA auto parts. I asked the guy behind the counter about sellin "battery fluid", to sound ignorant. He said they sell 5 gallons of I'm thinkin around 30% sulfuric acid for $30. It's a little pricey, especially considering I'll only have 1.5 gallons of concentrated acid, after boiling.

He said the 5 gals was for companies that use large machinines like bulldozers and such, so he might wonder why I'm buying it, especially since the area has a little "meth lab problem."

I'm not going to use drain cleaner acid for sulfuric in explosives synthesis anymore, it's always black after boiling, no matter what brand (probably beacause of the inhibitors they put in) so it makes it hard to see the true colors and whats going on in a reaction.

I only use drain opener)un-pure) sulfuric acid for making nitric in distillation, due to the process and no added chemicals get into the final and wonderous product.

[ALENGOSVIG1]

Try filtering it through asbestos, glass wool or mabe skarksin in a buchner funnel.

[blindreeper]

Thanks for the imput guys but I solved my H₂SO₄ problem about half an hour ago. My mum went to the dump to err...dump stuff and there is a special place for car batteries. I went over and started to put the biggest batteries in the car and when I moved one I almost shitted myself. Just there was a 2.5L bottle labled SULPHURIC ACID. So I picked it up and it was full!!!!! So now I have 5 batteries worth of sulfuric acid and 2.5 L of sulfuric. It is sulfuric acid in there cause my dad had a sniff and says thats definatly sulfuric acid. What concentration could I expect from this bottle? There was no concentration on the bottle, but it said BATTERY GRADE SULPHURIC ACID. I will boil it to the point of white fumes. I also got some KNO₃ and some ammonium nitrate so I might nitrate some cotton or toilet paper (unused of course) There was also a 5 L container of 35% HCl so I snatched that up aswell. :D

<small>[ December 07, 2002, 08:26 AM: Message edited by: blindreeper ]</small>

[knowledgehungry]

Battery grade is 30%.

[Mr Cool]

Nitrated tissue paper makes a good acid filter, that's what I use when I need to filter strong acids.

[kingspaz]

blind reeper, don't forget to charge all the batteries for 12 hours each before you empty them. if you don't do that step then you will get barely any acid out of them. you also must empty them straight after charging incase the H2SO4 content drops. this will happen if the battery is a dud, most batteries there have been put there for a reason. plastic buckets will be fine because its not high concentration. also you can use a t-shirt or filter paper.

[blindreeper]

I also read that concentrated sulfuric acid is a very good dehydrating agent. So once I boil the acid down to 98% stuff, will it readily absorb water from the air and dilute it? I was reading some old posts and one said make sure there are no scratches in the pot/conatiner whilst boiling it down, because it may crack = Bad :( But since I'm using borosilicate glass (pyrex) will it matter if there are minute scratches on the glass surface? I'm putting the batteries on the charger now. From say 1L of 30% sulfuric acid, how much concentrated acid can I expect, not much?

[CyclonitePyro]

You should get just a little over 300mL of 98% sulfuric acid.

Thats a nice find you got yourself, I'd love to find a heap of car batteries and even more a bottle of the acid conveniently taken out for you.

So asbestos, glass wool and nitrated tissue paper will remove the color from my acid, if this is true thank you ALENGOSVIG1 and Mr Cool very much. As a coincidence I have purchased a 500mL and 1L filter flask and small and large buchner funnels.
Where might one buy nitrated tissue paper, I'm not about to use my HNO3 to nitrate some kleenex <img border="0" title="" alt="[Eek!]" src="eek.gif" />

[ALENGOSVIG1]

I havent tried any of the methods i posted, but ive been told they work. No promises though.

[Sam]

Whoah, your in Australia and you can buy that much &gt;90% nitric acid for that cheap? Where the hell from? I have searched all over N.S.W. and never even seen it for sale in any concentration!

[frogfot]

How would one remove Pb from battery acid? Will electrolysis with carbon rods do it to convert it to PbO₂?

EDIT: Sorry, I'll shut up now <img border="0" title="" alt="[Frown]" src="frown.gif" />

<small>[ December 08, 2002, 06:01 PM: Message edited by: frogfot ]</small>

[blindreeper]

Well in the Brisbane area ( GO QUEENSLANDER!!!!). It's from an agricultural place called Grow Force Australia. The same place where I got my KNO₃. I don't know what it's sold for probably making nitrate fertilizers. I'll have to get my mum to go in and buy it cause if I go in "Son, what do you need 15L of nitric aicd for?" it will look bad, cause i'm only 13. Their site is <a href="http://www.growforce.com.au" target="_blank">www.growforce.com.au</a> The battery acid wasn't removed from batteries it's for filling up old ones so it has no impuritis. I think I will boild this 2.5 L bottle down first. Then if I havn't enough I will then boil the stuff from the batteries down.

[kingspaz]

frogfot, read the whole topic :mad:

[Fukineh]

Oh precious nitric acid. If I could get 90% HNO3 I would be one step closer to utter completeness. I was gonna say don't waste it making H2SO4, but with 15 L its not such a crime to use some of it up.

[VX]

blindreeper It does matter if their are small scratches on the glass, not because of the effect of sulphuric acid or any other chemical on it but because they massively increase the chance of the glass shattering due to thermal shock or small knocks etc. However if you are careful and heat it slowly and avoid mechanical impacts to the glass you should be OK. Just remember the last thing you want is boiling conc. sulphuric acid spilt everywhere, or anywhere for that matter.

Also it seems interesting that your dad could conclude that your mystery solution was in fact H2SO4 with such conviction from its smell when H2SO4 has no smell.

Finally H2SO4 is an excellent dehydrating agent and it will quite happily absorb moisture from the atmosphere to dilute itself. As such it should always be kept in a closed container.

Edit: Spelling

<small>[ December 12, 2002, 10:24 AM: Message edited by: VX ]</small>

[blindreeper]

Yes the last thing you want is boiling 98% sulfuric acid on your skin. I was takin it off the bunsen and a bit splashed on me finger. That was on tuesday I think and I have a small hole in my skin = :mad: I tried out that manganese heptoxide, very fun stuff. Also what would be more effective at boiling down the sulfuric acid? A 500 mL beaker or a 500 mL flask? I want to know cause I want the faster method for obvious reasons.

[VX]

A heat source would probably be more effective than either of the two <img border="0" title="" alt="[Wink]" src="wink.gif" /> . The safest option though, is whatever has the larger opening at the top so it's probably going to be the beaker. Be careful not to fill it more than about half full, and with boiling acid you could really do with something to act as anti bumping granules, try a few tiny pieces of broken glass. Preferably very scratched (sand blasted?)

The only other thing to say is that Manganese heptoxide may well be ‘fun stuff’ but if you can’t even manage to boil sulphuric acid without causing injury to yourself then you should not be making it for quite a while yet.

[nbk2000]

Unless, of course, he's willing to share with us the results of his "Mn Heptoxide and the flammibility of human skin" experiment when some gets splashed on him.

<img border="0" title="" alt="[Wink]" src="wink.gif" /> :D

<small>[ December 13, 2002, 08:58 AM: Message edited by: nbk2000 ]</small>

[blindreeper]

Well I got a cotton ball and mixed it with some very fine KMnO₄ and put it on the ground. I dropped some of the 98% sulfuric acid on it and after about a second it started fizzing and flames shot out of the sides of the cotton ball. It was instantly vaporized <img border="0" title="" alt="[Eek!]" src="eek.gif" /> But the thing that confused me the most was during the burning stage a brown purple gas/smoke came off, then a bright pink/purple smoke came off. What is this purple smoke from? I'm guessing it's from the KMnO₄ but i'm not sure.

[VX]

Right, it's got to be said. Do a Search for manganese heptoxide, and you will see! There has been a lot written about this compound and you are asking the same questions over again. :mad: To be honest I’m surprised that nobody has said this sooner.

[Trinitrotoluene]

I am wondering is it possable to make H2SO4 for NaHSO4? After HNO3 is made with H2SO4 and NaNO3 to get HNO3 and a byproduct NaHSO4. I've heard heating it will cause it to decompose to SO3 and I guess the So3 can be dissolved into water to produce H2SO4.

[rikkitikkitavi]

NaHSO4 decomposes at around 300 C.

2 NaHSO4 =&gt; Na2S2O7 + H2O (sodium pyrosulfate)

Sodium pyrosulfate decomposes at 350 C and higher

Na2S2O7 =&gt; Na2SO4 + SO3

Beware that these salts are very corrosive when molten, they are used to dissolve metal ores for analysis!

Ps NaHSO4 decomposes into Na2SO4 and H2SO4 by extraction with 80 % EtOH. The former is insoluble in the liquid and the latter goes into solution. There are some patents covering this (I have forgotten the numbers)

/rickard