text: Not sure of the exact specs, they would depend on the concentration of ammonia in air and how much total ammonia you expect to scrub before recharging the scrubber.\n\nAmmonia is very soluble in water, more so in acid.  Dissolve an acid in water (doesn't really matter which one, cheap HCl, sulfuric, acetic, all work--don't use nitric, ammonium nitrate can be explosive).  Put the aqueous acid in a flask.  Run the air to be scrubbed through a tube into the water.  The air should come out pretty clean of ammonia.\n\nThe acid helps keeps the ammonia from re-volatilizing from the solution.