6. Absorption of NOx from aqueous solutions

6.1 Reaction mechanisms

As already stated, according to the most commonly accepted reaction mechanisms of NO _x absorption in aqueous solutions, nitrogen oxides are made up of several species among which we distinguish, in ascending order of solubility in the aqueous phase, nitrogen monoxide NO, nitrogen dioxide NO ₂ and nitrogen tetraoxide N ₂ O ₄ , nitrogen trioxide N ₂ O ₃ and nitrous acid HNO ₂ (which can form in the presence of water vapor).

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