distilling nitric acid

[Geo]

i have done this many times (more than i can remember) but even though i know the process very well the exact ratios of the reagents is still unclear to me. I've searched the forum for the ratios with no luck and even a web search was no help. i have been mixing one standard cup of each reagent (potassium nitrate + sulfuric acid) and recover one standard cup of very strong nitric acid. i feel i am wasting one reagent or the other and I'm leaning toward the sulfuric being wasted the most. i know i should be measuring the chemicals by weight rather than by volume and I'm hoping one of our chemist can give me a definitive ratio of reagents to use. the recovered amount is the most important thing to me and that's why i make what i need as i need it . i purchased a five gallon container from Brenntag last summer but i still have twenty pounds of potassium nitrate and two gallons of concentrated sulfuric i would love to use up.

 

[lazersteve]

Distilling Nitric Acid Ratios

Steve

 

[Geo]

thank you very much Steve. for some reason my searches kept coming up with a lot of different things. i can understand how a new person can get frustrated trying to search through all the topics.

 

[butcher]

Years ago Laser Steve worked out the math (mole ratio's) to make nitric acid (cold method),
A simple forum search will disclose this gem, all older members should already Know it and help new members to find it.
He also considered the solubility of the salts formed from the reaction, as when making the more concentrated acid the bisulfate salt becomes more soluble and this is not desired, so by making the 50% concentration most of the salts are sodium or potassium sulfate, much less soluble and easier to separate from the nitric acid than the bisulfate salts.


Here is a clue to how to find the formula’s that will work the best, it should be easily found by any new member looking for information as we always try to point them to find and read these documents.

Found as sticky post in general reaction section,
Forum general reaction list:

http://goldrefiningforum.com/phpBB3/viewtopic.php?t=562
links to other recipe's is in blue links.

I fear if we as members do not do a better job of helping new members study and find what is provided here on the forum, we can lose the forum as we know it, a place to learn new and useful information, (not a place to answer the easily found answer over and over again),

So next time some new member asks how to make nitric acid, or correct ratio’s we can tell them see the general reaction list.

And my favorite:
Read Hoke’s Book.