Sciencemadness Discussion Board

Fuming Nitric Acid

Plankton - 3-1-2010 at 10:23

I'm looking for a good price on 2.5L of fuming nitric acid. I use this for decapsulating electronic components. The best price I've found is $325 from Puritan Products Chemical Co. This includes shipping fee of $120. :o
I'm about to pull the trigger on this deal but I want to be sure there isn't a more economical option.

Thanks,
Fabian
http://www.icdetect.com

Plankton - 3-1-2010 at 10:33

BTW... I'm located in the USA. (South Texas)

Fleaker - 3-1-2010 at 13:18

Does it need to be ''fuming''? By that do you mean white fuming or red fuming nitric acid? I know nothing about decapsulating electronic components but plenty about nitric acid! Do you absolutely need 90%+ or would regular reagent grade 16M (~70% w/v) work?

hissingnoise - 3-1-2010 at 14:28

Puritan lists RFNA for decapsulation but $325 for 2.5L is very high.
But if you wanted to produce it, or concentrate 70% acid yourself you'd need some kind of permit to do it legally.
Would that be an option?

Plankton - 3-1-2010 at 16:10

The manufacturer of the decapsulator recommends 90 - 98 % Nitric Acid. The decapsulator is basically an etcher that uses a micro pulsating jet stream of nitric acid heated to 90 deg. C to create a cavity in a electronic component by removing plastic material. I asked tech support if I could use 70% and they said no.

The $325 quote is for 90% Nitric Acid. The 98% Red Fuming Nitric Acid is even more expensive.

Producing it is not an option for me.


[Edited on 1-4-2010 by Plankton]

Jor - 3-1-2010 at 16:18

Not sure if you're a hobbyist, but make damn sure you have good ventilation when using fuming nitric! Especially the red version.

Plankton - 3-1-2010 at 16:31

I have a ductless fume hood with a filter designed for fuming nitric and sulfuric acids. I'm a start up small business looking to save some cash.

User - 4-1-2010 at 04:12

Making it yourself would indeed be far cheaper.
Vacuum distillation of H2SO4 and K/NaNO3 gives almost WFNA which you can free from NOx by adding urea.
Although if youre going to heat it as high as 90 degrees the formation of NOx will happen anyway.
There is plenty of info on this forum about the procedure.
I can imagine that if you have equipment like you described this procedure can be performed without to much trouble.



[Edited on 4-1-2010 by User]

hissingnoise - 4-1-2010 at 06:50

Quote: Originally posted by Plankton  
I'm a start up small business looking to save some cash.

As user said, making HNO3 yourself would certainly save you money.
The minor investment in glassware would pay for itself in no time.
And the savings could be considerable. . .


Plankton - 4-1-2010 at 09:22

I hadn't entertained the idea of making Nitric Acid but I guess I've found the right place to learn. This should be interesting.

Thanks....

hissingnoise - 4-1-2010 at 12:56

This could get you started, or it could turn you off the idea. .

www.youtube.com/watch?v=CtdX5YmOdcs

mr.crow - 4-1-2010 at 13:11

I am sure your business is already set up as a laboratory, so a fume hood with a distillation apparatus wouldn't be a big deal.

Sulfuric acid and nitrates are easy to get and very stable. Fuming nitric acid is very unstable and corrosive so a 2.5L bottle would be problematic unless you used it all right away.

Can you take 100x microscope photos of chips for reverse engineering?

Contrabasso - 4-1-2010 at 13:16

Just be VERY careful that you are safe with the acid. The fumes are both an acute hazard AND a chronic (long term) hazard. You could be "investing" your long term health in making a quick buck.

The reason why it seems profitable may be because it's too dangerous for fully compliant industry to contemplate.

Plankton - 4-1-2010 at 14:28

Contra as I've read through some the the info on making FNA and watched videos on youtube; I've decided that based on time constraints, it is best for me to purchase the stuff. Once I hire someone to help with the administrative stuff, I may give this a whirl.

Plankton - 4-1-2010 at 14:34

Quote: Originally posted by mr.crow  

Can you take 100x microscope photos of chips for reverse engineering?


Mr. Crow,
I can take photos up to 400X in both BF and DF. I use a Nikon Optiphot metallurgical microscope.

hissingnoise - 4-1-2010 at 14:36

Yes, time lost at a crucial stage could be very costly and 2.5L would, I'd say, decapsulate a good number of devices.

bquirky - 5-1-2010 at 00:07

can you do passport RFID's aswell ?

I jest.. i jest :)


densest - 5-1-2010 at 22:11

There's a chemical supply house in Oklahoma which specializes in nitric acid including RF. PM me if you want the name. Very easy to deal with if you're professional about it. They may call you to ask what you're doing to protect themselves but you are clearly being businesslike and should have no problems.

jgourlay - 11-1-2010 at 18:11

Hissingnoise: two questions about that video. First, is there any grease or other "stuff" put into those glass on glass connections. Seems.....leaky leaky. But I don't have any experience w/ground glass connections. Two, how do you draw that vacuum without getting gawd knows what INTO the vacuum pump?

hissingnoise - 12-1-2010 at 06:25

I haven't tried vacuum distillation for HNO3 because I don't think it's really necessary.
I used to use a thin smear of vaseline on male connections but there was always some slight bubbling and a yellow coloured nitrate on the ground-glass.
I've since found that a few turns of teflon tape works much better.
Glindemann rings would be better still.
If I were to try vacuum, it'd have to be an aspirator as I couldn't afford to buy a pump that would be impervious to corrosive vapours.
A cheaper pump could be protected somewhat by a couple of wash-bottles with the one closest to the pump containing H2SO4 to trap acidic moisture.
But anyway HNO3 from KNO3/H2SO4 at normal pressure is strong enough for any nitrations I'd want to do.




[Edited on 12-1-2010 by hissingnoise]