DIY Nitric Acid

[oldguy]

Is this a reputable method, any pro's, con's?

 

Nitric acid Reaction:

-Bring 100 mL of Distilled Water in a 500 mL pyrex beaker to 212F (100 C)

-Add the Nitre of your choice (202 gm K / 170 gm Na)

-Stir until Nitre is completely dissolved, let cool below boiling

-SLOWLY add 56 mL concentrated (96%+) Sulfuric Acid to Hot Nitre solution while stirring. DON'T allow the solution to boil!

-Allow solution to cool to room temp (DO NOT SKIP - VESSEL WILL SHATTER IF PUT ON ICE WHILE HOT!!!)

-When vessel reaches room temp 77F (25 °C). Put the vessel in the freezer or on a salt water ice bath

-Let stand until temperature of mixture reaches -41F (-5 °C)

-Let stand at -41F (-5 °) until all precipitate settles

-Pour the COLD solution off into glass container with tightly sealed lid DO NOT POUR OFF ANY OF THE SALT IN THE BOTTOM!!!

Makes ~160 mL ~ 50% HNO3

 

 

[anapogeetoofar]

Depends on what you want to use the acid for.

 

For use as an etching agent or for dissolving metals? Yes.

Anything sensitive to H2SO4/sulfate contaminants? No.

 

It does work though to a certain extent, Ive used a similar method using CAN fertilizer to make acid around 60% as calcium sulfate is almost insoluble. I only used it to dissolve lead and copper though. Tried it using sodium nitrate and ended up with more lead sulfate than nitrate when I tried to use it.

 

Make sure to use either calcium or sodium nitrate, not sure how well potassium nitrate would work.

[pyrojig]

Depends on what you want to use the acid for.

 

For use as an etching agent or for dissolving metals? Yes.

Anything sensitive to H2SO4/sulfate contaminants? No.

 

It does work though to a certain extent, Ive used a similar method using CAN fertilizer to make acid around 60% as calcium sulfate is almost insoluble. I only used it to dissolve lead and copper though. Tried it using sodium nitrate and ended up with more lead sulfate than nitrate when I tried to use it.

 

Make sure to use either calcium or sodium nitrate, not sure how well potassium nitrate would work.

 

From what I have read barium nitrate is the best choice of nitrate, second is sodium nitrate. Kno3 is the easiest one to get for most of us in bulk, and will make very good acid.

Edited June 16, 2011 by pyrojig

[Mumbles]

There is one big problem with that method, in my opinion. All protons on sulfuric acid are not created equally. The first protonation is very strong, but the second one is not enough from the literature to protonate the second mole of nitrate. Heat can force the issue, but I'd be wanting to use a 1:1 molar ratio instead of 1:2. There is something significantly wrong with some of their math too. If that works, it should give around 80% nitric (assuming full conversion), and I do believe the celcius and Fahrenheit are backwards.

 

I've never given much credibility to these corner cutting methods. In my eyes, if you really want nitric acid you will either have to distill it, or extract with DCM.

 

The issue with using a nitrate source which forms an insoluble sulfate at RT, is that it tends to really clog things up and trap a lot of acid.

[oldguy]

There is one big problem with that method, in my opinion. All protons on sulfuric acid are not created equally. The first protonation is very strong, but the second one is not enough from the literature to protonate the second mole of nitrate. Heat can force the issue, but I'd be wanting to use a 1:1 molar ratio instead of 1:2. There is something significantly wrong with some of their math too. If that works, it should give around 80% nitric (assuming full conversion), and I do believe the celcius and Fahrenheit are backwards.

 

I've never given much credibility to these corner cutting methods. In my eyes, if you really want nitric acid you will either have to distill it, or extract with DCM.

 

The issue with using a nitrate source which forms an insoluble sulfate at RT, is that it tends to really clog things up and trap a lot of acid.

 

So with a good distillation setup & fume hood, you add nitrate and conc sulfuric (NO water!) and gently distil off conc nitric.

 

The object here is to nitrate Microcrystalline Cellulose.

 

 

[NightHawkInLight]

Nitric acid is simple enough to distil from a sulfuric/nitrate mixture. All it takes is heating it in one flask with a glass tube connecting to another sitting in an ice bath. Nothing to it. The trickiest part is not splashing it on yourself as you tear down your setup.

 

Just an example to how easy it is to make, years ago I mixed up a sulfuric/nitrate slurry in a beer bottle, duct taped another bottle mouth to mouth, then heated the acid containing bottle over a gas burner while I draped a ziploc bag full of saltwater and ice over the empty one. Distilled out about 50 mL of moderately high concentrate nitric in no time. While it was obscenely dangerous to heat an acid bath over open flame in non heat resistant glass, it worked. If my redneck self can make it with a few beer bottles and duct tape think of how easily it could be done with $20 worth of actual glassware.

[usapyro]

Nitric acid is simple enough to distil from a sulfuric/nitrate mixture. All it takes is heating it in one flask with a glass tube connecting to another sitting in an ice bath. Nothing to it. The trickiest part is not splashing it on yourself as you tear down your setup.

 

Just an example to how easy it is to make, years ago I mixed up a sulfuric/nitrate slurry in a beer bottle, duct taped another bottle mouth to mouth, then heated the acid containing bottle over a gas burner while I draped a ziploc bag full of saltwater and ice over the empty one. Distilled out about 50 mL of moderately high concentrate nitric in no time. While it was obscenely dangerous to heat an acid bath over open flame in non heat resistant glass, it worked. If my redneck self can make it with a few beer bottles and duct tape think of how easily it could be done with $20 worth of actual glassware.

 

O.o That's a very interesting way to do it. What ratio of nitrate to sulfuric were you using? 1:1? And how exactly did you check the temperature so you would know when all of the nitric acid is boiled off?

[oldguy]

I bought 1 lb of MCNC from a private source. Everybody would laugh at the price I paid. Now, I need more, but don’t want a nose bleed over the expense.

 

I’m still trying to figure out a relatively simple safe way to DIY MCNC.

 

Sulfuric acid is readily available in bulk @ a very reasonable price per gallon. I can safely concentrate it in a an old style 70’s stove top thick Pyrex 12 cup coffee pot on a lab grade hot plate with a temp control setting dial in the middle of 40 acres. So, fumes or danger to other persons, or others property is not an issue. I have numerous nitrates in bulk. I have a bulk source of MCC & several lbs on hand.

 

What I need to know is at what temp do you boil battery grade Sulfuric acid & for how long for an acceptable concentration range.

 

Which nitrate is best?

 

What volume to what volume (or in parts) do you add.

 

I assume you agitate or stir the mixture under heat until the nitrate is dissolved?

(what temp?)

 

Once that’s done, distilling off the nitric acid into a compatible container is relatively simple.

 

Now what?

 

How much MCC to how much nitric acid under what conditions to get pyro grade MCNC?

 

(this is for a smokeless and or low smoke flare comp)

 

Assuming I get this far?

 

I gather you safely pour off as much nitric acid as possible into a separate compatible container.

 

Then I gather you flood the container containing the MCNC with a continuous gentle flow of clean water for an extended time to dilute & remove the remaining nitric acid.

 

I can give it a 2^nd separate wash on a magnetic stir plate.

 

I can handle it from there with filter paper & a Buchner funnel to remove the MCNC.

 

FYI, I have a long acid resistant apron, shoulder length acid resistant gloves, a full face shied & respirator.

Years back I did considerable work with cyanide, in heap leach gold recovery systems. So, I have experience with toxic chemicals & mixes.

 

I realize this is a sensitive subject, because these chemicals are not something kids or irresponsible people should fool with.

If anyone doesn’t care to publicly post any pointers, please be so kind as to privately PM me.

I would be very grateful one way or the other.

 

 

[madmandotcom]

another method is to use 80 grams Xno3, 30 grams nitrate salt and 100 millilitres of hydrochloric or sulphuric acid in one end of a gas generator and water or hydroen peroxide in the other

[Mumbles]

another method is to use 80 grams Xno3, 30 grams nitrate salt and 100 millilitres of hydrochloric or sulphuric acid in one end of a gas generator and water or hydroen peroxide in the other

 

Any references or theory behind this method?

 

I'll get to some of the questions you posted later oldguy. I have a few things to take care of today, and I was just checking through the forum quickly.

[madmandotcom]

Any references or theory behind this method?

reference: nurdrage theory: nitrogen dioxide through the water/peroxide creating nitric acid

[Mumbles]

Ahhhhhh. That is what we in the trade call shitty science.

[madmandotcom]

it does create a copper disolving acid and the only acid that can dissolve copper is nitric, therefor it has to be nitric

[Blackthumb]

Isn't HNO3 sold anymore??? Watched a student almost lose his eyes and face doing a similar stunt. I was a chemistry major and would rather smoke a pipe while pounding rockets than expose myself to the dangers above for a little HNO3.....

Been handling nasty 'stuff' for over forty years....made nitro and guncotton... still have my eyes and fingers.....can't hear worth a damn though since I learned 70/30!

[Mumbles]

Even 2% nitric acid dissolves copper, which is probably in the ball park of what that method produces. If you bothered to read above, and rewatch the video, he would like to make MCNC; microcrystalline nitrocellulose. I'll save you the hours of research and reading you're likely to do on the subject, and let you know that nitrations do not work with dilute nitric acid. They don't even work with 70% acid. Before your great chemistry knowledge tries to counteract that statement, this is one of the purposes of sulfuric acid in nitration mixes. It absorbs water out of the nitric acid making it significantly more concentrated in actuality. It is why some more sensitive nitrations must use 95% nitric acid, or other special dessicants.

 

I'll try to address the questions in order.

 

Concentrating sulfuric acid requires fairly high temperatures. I believe somewhere in the vicinity of 300C to get up to 98%. One of the typical ways to tell when it's done is to watch for characteristic thick white fumes, known as "acid mist", which is aerosol sulfuric acid.

 

As far as nitrates, any will really do. IMO sodium nitrate is the best, as it has the most nitrate for your buck. Ammonium nitrate I tend to not care for. I'm always afraid I'll heat it too high and decompose the ammonium (bi)sulfate. They're all pretty cheap though.

 

A typical nitration mix is 1:3 nitric acid:sulfuric acid. This is for 70% nitric and 98% sulfuric.

 

The best way to distill nitric acid is under vacuum. With a good vacuum, you don't need to heat it at all actually if you have the receiving flask in an ice bath. Otherwise, it's generally considered best to keep the heat low, and distill for a long time. Typically 100C or less if you're distilling high concentration. I know of people who have done it at 60C, and have just relied upon the vapor pressure of nitric acid to slowly distill it over. Doing this gives fairly clean acid actually. Something to note, you need an all glass setup to distill nitric acid. The hot acid attacks pretty much anything but glass and teflon. I've ghetto rigged setups using rubber stoppers, which would usually dissolve to a goo by wrapping with a healthy layer of teflon tape.

 

I'll get back to you on ratios. I used about 60mL total nitration mix (IIRC) for 5g of cotton before. Typically one uses an over kill amount as the acid is dilluted during the nitration, and never goes to full stoichiometric conversion. I'd go probably 1:6 or even 9 molar ratio of cotton to nitric acid.

 

Once the nitration is done (1-3hr probably), typically the nitration mix is drowned with water, at least 10x the volume. Let the solid settle, and decant. I'd wash with water at least 3 more times. Then wash with bicarbonate solution, and perhaps let it stir overnight. Wash with water 1-2 more times. I usually like to wash with a urea solution too, which helps to stabilize the nitrated cotton.

 

I'll say this now. Making 5-10g of NC is a FAR different animal than doing pounds or kilos. There are relatively few people on the earth with the knowledge to do it truly safely and effectively. I lucked out and was shown proper techniques, and have effectively done around a kilo before.

[Peret]

Isn't HNO3 sold anymore??? Watched a student almost lose his eyes and face doing a similar stunt. I was a chemistry major and would rather smoke a pipe while pounding rockets than expose myself to the dangers above for a little HNO3.....

Yeah, it's available. So is concentrated sulfuric. I'm sure these are not the best prices you could find, but it's very convenient. I personally prefer to spend more for quality reagents for this kind of project, rather than make my own and really have no idea whether the reaction is going by the book.

[FrankRizzo]

Unless you have a healthy curiosity for how things are made and want to do it better, if you consider the processing risks and the cleanup worth anything, it's usually best to pay someone else to do the dirty work at an industrial scale.

[oldguy]

Unless you have a healthy curiosity for how things are made and want to do it better, if you consider the processing risks and the cleanup worth anything, it's usually best to pay someone else to do the dirty work at an industrial scale.

 

 

True, but the cash out of pocket cost will make both your nose & wallet bleed.

I only need about a kilo, which if made in about 4 seperate batches, isn't to tough.

 

 

This will help some.

I tested it & its reasonably precise.

Edited June 19, 2011 by oldguy

[oldguy]

http://knygos.sprogmenys.net/knygos-2/Explosives/Science%20of%20Explosives/Chemistry%20and%20Technology%20of%20Explosives%20-%20vol%201%20-%20Urbanski.pdf

645 pages

[MadMax]

OG,

 

If you're trying to nitrate MCC would it make sense to try adding the MCC directly to a mixture of high conc sulfuric acid with a nitrate salt? I seem to remember reading somewhere this being a viable solution for nitration without the need for nitric acid.

[madmandotcom]

Even 2% nitric acid dissolves copper, which is probably in the ball park of what that method produces. If you bothered to read above, and rewatch the video, he would like to make MCNC; microcrystalline nitrocellulose. I'll save you the hours of research and reading you're likely to do on the subject, and let you know that nitrations do not work with dilute nitric acid. They don't even work with 70% acid. Before your great chemistry knowledge tries to counteract that statement, this is one of the purposes of sulfuric acid in nitration mixes. It absorbs water out of the nitric acid making it significantly more concentrated in actuality. It is why some more sensitive nitrations must use 95% nitric acid, or other special dessicants.

hydrochloric will create low conc. acid, sulfuric will create 90%+, it is the same method used in this video, he is a respected chemist and has receive no negative feedback on his video

[Mumbles]

That's probably because anyone trying to learn chemistry from Youtube or use it as a viable resource doesn't know any better. Check science madness if you want to see people who really know chemistry interacting with him.

 

You cannot isolate 90+% nitric acid without distillation. Regardless of the acid used in the generation of NO2, the final concentration formed by this method will be extremely low, and not viable for any real uses.

[madmandotcom]

the link dint load hang on

[jimbo]

hey madmandotcom,those methods for nitric are woeful,I'm putting together a distillation kit to get almost pure nitric,there are way better video's on youtube showing nitric production,I just need some retort stands and clamps to get it going,I got this set for about $200.

[r1dermon]

http://www.chemical-supermarket.com/Nitric-Acid-White-Fuming-250ml-p521.html