Get rid of NOx fumes and get stronger nitric acid

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Staff member
Jan 6, 2008
Pacific NW
we have been discussing making nitric go further and trying to reduce the gases from the reaction, so, I do not want to confuse anyone with this statement:

But sometimes I will actually try to make more NOx gas from some of the things, or reactions I use, or do, I can recover these gases to make a dilute nitric acid with, that can be concentrated and reused...

Example when working with nitrate salts and acid in a recovery method, I may actually purposely try to create more NOx gas in the reaction, with capturing these gases and bubbling them through a little water with a little H2O2, I can make some nitric acid as a byproduct...

For example:
Killing two birds with one rock is a process where I use a reaction to dissolve copper from pins plated with gold, Using a nitrate salt and sulfuric acid, in this process I make a byproduct of nitric acid, and another useful byproduct of copper sulfate, as I recover the gold foils from the plated pins, nothing goes to waste, and if done right there are almost no (or very little) dangerous fumes escaping to pollute the environment during the process...


Well-known member
Jan 22, 2014
Sicily Island
  • Process for making a silver nitrate solution
  • Last paragraph in Summary of the invention section said:
    Surprisingly it has also been found that in addition to the improved nitric acid efficiency and elimination of NOx fumes, the process provides an additional purification step due to the precipitation of contained impurities, such as copper and palladium, if present.

Does anyone have more information about this? If the above is correct things change a lot when you are also after palladium or want to separate them.