# Nitric Acid Purification

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Hey there - I was searching the net for ways to synthesize concentrated nitric acid (98%). The only methods I have come across so far have been synthesis by 98% Sulfuric Acid and some plastic sheet that can stand hot HN03, a 1000 ml beaker, a caculated amount of nitrate, and a 100ml beaker. You have to keep the beaker in the middle of the big beaker, and pour nitrate and the H2S04 mix around the small beaker and put the platsic foil over the whole thing and make sure it bulges in a bit and then lit it hang over the little beakers in the middle and it then hast to be secured with a rubber band and then it should be filled with ice water. After heat is given by a hot plate, the red fumes form and the acid evaporates.

I have 70% HN03 and I wanted an easier way to purify it to 98%+ Nitric Acid. If anyone knows a way to purify this, it will be a lot easier than synthesizing 98% Nitric Acid from H2S04.

THanks

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If you are going to make a bomb, as it sounds like, then please make sure you are in a remote part of arizona, and have your will written out first.

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O_o

using other peoples' brains for a bomb? that wouldn't be very smart now would it;)

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Add your 70% nitric to more 98% sulphuric and redistil it, youll get your 98% nitric but not higher as it forms an azeotrope with water. the addition of Urea will absorb any NOx radicals too, leaving a near pure product

If your trying to make some "energetic material" I can think of only one that requires that conc of Nitric, and beleive me you DONT want to play around with RDX!

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Are you serious, you searched the net for how long? 10 seconds?

Whatever....

Their are two ways of obtaining high purity nitric acid, one is to obtain a nitrate salt and mix it with an equal mass of sulfuric acid, then distilling this over to get around 91-95% purity, this is detailed a significant amount on the web and you should have no trouble finding it in either a text form or a video format(YOUTUBE), the only problem is having a distilling apparatus which apparently you do not have along with the experience to have any inkling on how to make such a simple chemical which basically means you should NOT be doing this reaction as you will, almost certainly, hurt yourself.

If your going to be dumb you better be tough(or at least try less dangerous things till you create a chemical so goddamn dangerous)

The second way of producing high purity(up to 98%) is to take already made nitric acid wether it be 68% or 92% and to mix it with an amount of either magnesium nitrate(recommended as in my experience it is significantly cheaper than sulfuric acid) or sulfuric acid, I will leave the exact amount up to you to figure out. The purpose of this is to remove the azeotrope(don't know what that is, DON'T do this) that is formed when you reach a 68% purity, this is done by the dehydration of the water in the azeotrope. Then you take this and distill it over, the only problem is that to reach a 98% purity you have to distill under a vacuum to keep down the decomposition of nitric acid into NO2 as this will contaminate your product, however you can still reach around a 96% purity without a vacuum as long as you control the temperature.

Finally, DO NOT MAKE EXPLOSIVES, you clearly do understand to much of chemistry or you would not be asking this question(not that that is a bad thing) and you clearly have a ways to go before you can create highly pure nitric acid, because of not only the skill required but also the apparatus. You would only end up with missing fingers if you tried to make explosives now!!!!

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I would think that in the almost 9 years since this was posted, the OP will have either died from their stupidity, gotten over their explosive making hobby or learnt a few lessons and survived to tell the tale. Good advice nonetheless.