Anyone Need A Little Fuming Nitric Acid?

If there’s a chemical with a cooler name than “fuming nitric acid,” we can’t think of it. Nearly pure nitric acid is useful stuff, especially if you’re in the business of making rocket fuels and explosives. But the low-end nitric acid commonly available tops out at about 68% pure, so if you want the good stuff, you’ll have to synthesize fuming nitric acid yourself. (And by “good stuff”, we mean be very careful with the resulting product.)

Fuming nitric acid comes in two colors – red fuming nitric acid (RFNA), which is about 90% pure and has some dissolved nitrogen oxides, giving it its reddish-brown color. White fuming nitric acid (WFNA) is the good stuff — more than 99% pure. Either one is rough stuff to work with — you don’t want to wear latex or nitrile gloves while using it. It’s not clear what [BarsMonster] needs the WFNA for, although he does mention etching some ICs. The synthesis is pretty straightforward, if a bit dangerous. An excess of sulfuric acid is added to potassium nitrate, and more or less pure nitric acid is distilled away from the resulting potassium sulfate. Careful temperature control is important, and [BarsMonster] seems to have gotten a good yield despite running out of ice.

We don’t feature too many straight chemistry hacks around here, but this one seemed gnarly enough to be interesting. We did have a Hackaday Prize entry a while back on improvements to the Haber process for producing ammonia, which curiously is the feedstock for commercial nitric acid production processes.

66 thoughts on “Anyone Need A Little Fuming Nitric Acid?

  1. Gotta run that Graham condenser vertically so the condensate doesn’t pool up in the spiral and cause backpressure, and so that the nitric acid all just runs straight out instead of requiring someone to fiddle with a fragile glass tube full of dangerous acid to shake out whatever is trapped in the coils.

  2. While that is unfortunate to hear, like electronics, chemistry is knowledge with both helpful and harmful applications. We should not close ourselves off to knowledge just because it may be misused.

    1. There comes a time when lifeboat ethics are the best choice. Taking the Wilson/Chamberlain “high” road gets you a bad case of death. How can you dehumanize the inhumane?

  3. Hammer attacks and van attacks are on the rise too, but we still post about those devices. I would agree with you if this acid were primarily intended as a weapon, but it’s useful for etching and such.

    1. fuming nitric acid is a very strong acid able to create powerful explosives. making explosives is not that difficult and with very basic products found in some stores, you can build very strong ones. Fertilizers and herbicides are powerful oxydants. Nitric acid is mainly used for creating fertilizers. A lot of chemical products can be used in 2 purposes; good or bad ones. It’s just a matter of knowledge and ability to obtain them.

  4. I’m doing the Haber process project on Hackaday.IO.

    I’m exploring a new attempt based on an obscure electrochemical reaction, which is proving difficult to reproduce. No results yet, I’ll write up the experiments after I either have results or become convinced that it won’t work.

    Been actively working on the new method with a group of people since about the first of the year, we’ve purchased a bunch of equipment, and have weekly meetings.

  5. I don’t believe for a second he needs this for PCB etching.
    68% is more than enough to dissolve copper. You could probably get by with half that or less if you mix sulfuric in with it.

    If he wants to do it because he can, sure, but PCB etching? There are dozens of ways to do it with less risk.

    1. White fuming Nitric is commonly used to eat mold compound that IC packages are made of. You heat the chip and apply it a drop at a time rinsing with DI water after each one. If there is copper present on the die, some high power analog have copper traces above the final passivization, you buffer your nitric acid with a 30-50% mixture of fuming sulfuric to slow the copper etch rate. This is annoying because you can’t use a plastic pipette once you add sulfuric acid and the glass ones always seem to give too big of drops >:(

      The point of this process is to etch away a divit exposing the die but leaving the rest of the chip intact including the leads and bond wires which is pretty easy to do for most packages after a little practice. This way you can power the die up and test it during operation. Of course then you get all the fun of light sensitivity of semi-conductor junctions and micro-scale capacitor plates.

      But yeah, Sulfuric is used to make Nitric acid LESS aggressive against copper.

      1. Odd since a number of patents cite the use of sulfuric with nitric acid in order to increase etch performance and minimize damage to the substrate. It has the benefit of absorbing any water in low % nitric acid and discouraging nitrous acid formation.
        As for plastic pipettes being incompatible with mixed acids, what? PP and or HDPE resist it just fine.

  6. Piranha solution is right up there in the cool chemical name shortlist. A mixture of sulfuric acid and hydrogen peroxide. Aggressively eats anything organic, hence the name.

  7. I’ve see this done better, and I finally found the video where Darian Berg avoids contamination from nitric acid breakdown products of the product by using cooling and vacuum distillation.

    As a general rule four of the best channels for learning chemistry are NurdRage NileRed DougsLab and Chem Player, there are others but they are either not very active these days or are messy in their work or unclear with their explanations even if they are successful in their reactions. The channels I have listed seem to be more “responsible” with safety and the choice of reactions that they explore, however most of what all of them do is very dangerous and should not be copied without a very good reason and due consideration of the potential consequences.

      1. Yes a small number of people have that problem, then again many like that voice, not sure what can be done about your disability though as that is one of the better quality systems they are using.

        This area is rapidly improving though but I doubt that they would redo their videos.

        You did notice that the full script of their dialogue is posted in the comments below the videos?

        1. “small number of people”,. “your disability”, riiiight.

          Now with the same cynism also tell me that bad playing or singing is a disability of the listener or that bad software is a feature not a bug.

          Don’t try to blame the viewers for your/his/her own disability/incompetence to do a passable voice over, even if it were sythesized.

          Alex Macintosh’s voice is more than 7 years old and as many others the speech is infinitely better, specially at prosody. The free Lisa one they use is really terrible. Heck even Microsoft’s Sam speech flow is better.

          1. Ever tried listening to Prof. Hawking? Even I can’t cope with that voice and slow speed of delivery! Oh and yeah it is a disability, get over it and stop being irrational, because many other people are more able to cope without the effort inducing irritation in them.

            I noticed that you avoided the point about the entire script being in the video comments anyway, so don’t expect any respect from me.

  8. You’re right, we should also stop all related multi-copter related posts because they have been used for criminals escaping prison. Also we should probably never talk about metal smithing again because criminals might make knifes or swords which as an English citizen you might know you guys have a SERIOUS stabbing issue. Oh and we defiantly shouldn’t talk about CNC or 3D printing because a criminal might make a gun or other illegal item. We should probably just stop everything because you know cars have been used for bombings and other idiotic nonsense.

    Seriously your an idiot and shouldn’t ever attempt to censor information as a CRIMINAL already has access to all this information I myself use legally obtained information for home defense technologies.Simple fact is anyone that wants to abuse information will, the internet has very “Dark” places there is nothing you can do to stop that. However HaD isn’t one of those places and comparing hobbyists to criminals makes you look stupid. Please just stop.

    1. That is one of the brighter signs so far. For some reason there have not been small drone attacks with Sparkfun and DHGate fragments spread all over. Fortunately there is a cultural demand to be a direct participant. Unfortunately that means that smart bombs look just like people and are just as smart.

  9. I made WFNA the same way ~15 ago. I was going to use it as an oxidizer in a liquid rocket engine. The fuel was terpentine which is hypergolic with WFNA. This stuff was so scary I never tested the engine, but switched to nitrous oxide instead.

  10. In the UK the majority of these acid attacks use a specific product which is readily available over the counter with no need to explain what you want to use it for, ID , or specialist licence. I just got asked how I was carrying it as I was on my motorcycle when I bought some for its intended purpose.

    So, no, this article isn’t dangerous to publish as is far easier to just buy an acid locally.

        1. Easy to make nitro usable as in Dynamite. And the nitrocellulose in smokeless powder is also soaked with nitroglycerine. It is very tough to set off by accident and it burns pretty slowly at 1 atm compared to the much less potent black powder.

  11. You would make a much better case if you were driven by knowledge of natural rights to life and property. Not killing people because you are emotionally disposed at the moment does not inspire confidence!

  12. Bedouin culture + Wahhabism = Death cult and fear of women and free will.

    Oil money used to spread Wahhabism far and wide has produced what we face today.

  13. The sort of idiots who’d throw acid at someone, are not the sort of person who’d be intelligent enough to supervise a dangerous chemical reaction, or even to get one going properly. Or understand the synthesis.

    This is something anyone who isn’t a fucking moron needs to remember about Muslims. Like every other type of person, there are decent ones, and a few dangerous cunts. There’s plenty of violent Christians and atheists in prison. I’ve no problem with throwing in violent Muslims too.

    But the vast majority are decent people, despite whatever horrible things you can copy-paste from their religious texts. Y’know, just like all those horrible bits in the Bible that sensible, modern, 21st-Century Christians don’t take seriously.

    Counting “Muslim” as describing a person’s personality is a category mistake that I’d expect better than, from anyone with any knowledge of science or maths.

    You might consider the KKK as an example of this principle, when applied to Christianity. Or you might carry on reading your Daily Mail, making up racist insults, and generally acting no better than our primitive forefathers, who pursued Race Science as fervently as Phrenology among those other wise pursuits of aging white men past.

  14. Back in the 1980s, most of our (Britain’s) terrorists were Irish. The IRA. Largely supported by donations from “Oirish” Americans. “Yeah, I’m Irish myself, my great-grandmother once visited Cork, and I really like eating potatos, paint me green”. As well as money they got from protection rackets perpetrated on their “own” people. And drug dealing and all the rest.

    So right now, most of the terrorism enacted upon the West, is carried out by Muslims. After a couple of decades of the West abusing Muslims, bombing their civilians from the sky instead of fighting like men, and generally letting them know their lives were worthless to us. After conspiring in their suffering when it suited us.

    But “all of a sudden” they get a bit pissed off with this and start attacking us.

    Muslim terrorists tend to come from dirt-poor countries. There are a few well-publicised exceptions, but that’s where it originates, and certainly where the anti-Western sentiment comes from. And, as ever, if you have a cause, you can dig up plenty of stuff from your Holy Book that supports it. Whatever the cause is, whoever you are, and whichever Holy Book.

    Since dirt-poor people tend not to have air forces, they use what they have an abundance of. People, who economically aren’t worth much. Indeed there’s been cases where people with mental disabilities have been encourage by their families to become “martyrs”. The family gets a martyr’s pension, and an unproductive halfwit out from under their feet.

    Rev them up with bullshit ideology, as well as a certain amount of threats and peer pressure, and strap on the dynamite.

    Our present terrorists are Muslim, because we’ve spent the last few decades bombing countries full of Muslims. It’s not even slightly difficult to figure out.

    We bomb them from the sky, so there’s absolutely no chance our soldiers can get hurt. Them not having air forces, or any sort of complex weapon (maybe an old RPG from the Soviet days). We don’t come down and arrest criminals in person, we bomb their village, and mumble about “collateral” or “casualties”, if anyone really gives a shit.

    This tells the average Muslim, that their lives are worth nothing to us. We will kill them, with no compunction, if it achieves one of our aims (often a really stupid aim that doesn’t help at all). This is surely unarguable.

    So then is it surprising when they start to get a bit pissed off, and want revenge? And that anger can be shaped by local demagogues into a usable force. You stir up the already existing fear and hatred, then organise and start sending martrys our to kill a few Westerners, whose only crime happened to be standing near an explosion.

    It’s evil and it’s not right, but it’s certainly fair.

    1. Just a footnote… the IRA killed many more human beings than Muslim terrorists have. Despite being white, and Catholic. What puts Catholicism on the edge of terrorism all the time? By “all the time” I mean during the 1970s and 80s but not any more. Did they edit the Bible in the 90s or something?

    2. “Muslim terrorists tend to come from dirt-poor countries.” Major terrorist leaders and many terrorist are from wealthy Saudi families and from those deeply involved in Wahhabi and the ubiquitous schools and mosques built by the Saudi’s – there are probably some near you.

      The Iran-Iraq war was hardly about the infidels dropping random bombs and it killed around 1.4 million. And the ISIS psychos are killing a LOT of Muslims for not being the right kind of Muslims. Your theory has an attractive simplicity, but it does not fit.

  15. I don’t think anyone would make white fuming nitric acid to throw at someone in the face. That’s like making your own bullets out of silver or something. Those guys commonly use some washing chemicals that can be purchased in the shop.

  16. Probably not fuming nitric acid. If all one wants to do is hurt somebody, a little bog standard car battery acid (sulfuric) is gonna be just as effective. Why would they bother synthesizing fuming nitric acid? This stuff has very specific uses, like de-capping ICs.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.