Sciencemadness Discussion Board

Absorption of Nitrogen Dioxide

SAM4CH - 27-11-2004 at 08:40

How can I reach to dissolve NO2 in water with great rate (up to 90%)? I ment what is the conditions!!

[Edited on 27-11-2004 by SAM4CH]

budullewraagh - 27-11-2004 at 09:12

use lechatlier's principle...increase pressure

SAM4CH - 29-11-2004 at 08:28

I know that but I ment the best conditions which allow to dissolve all NO2 in water! In home Tech.!!

BromicAcid - 29-11-2004 at 09:13

Quote:
How can I reach to dissolve NO2 in water with great rate (up to 90%)?

Things that can help would be an efficient bubbler. Not just an aquarium bubbler but an actual gas washing bottle with the glass frit in it, they make really tiny bubbles that are more easily absorbed and do not contaminate reaction products. A good gas wash bottle is a great investment. In addition remember that when nitrogen dioxide reacts with water it forms both nitrous and nitric acid. The nitrous acid readily leaving the solution in the form of nitrogen monoxide. To compensate for this it would be advisable to bubble air through the reaction mixture simultaneously to oxidize the nitrous acid formed in situ and to oxidize nitrogen monoxide as it escapes, because of this it might be a good idea to put two gas wash bottles in sequence to absorb the nitrogen dioxide/monoxide that escapes from the fist bottle, ending with a strong hydroxide solution to wash (don't use a good wash bottle, the NaOH will attack glass frit). Finally as budullewraagh said increasing the pressure will led to increased dissolution of the nitrogen dioxide. Addition of hydrogen peroxide will also aid in conversion of nitrous acid and nitrogen monoxide into your desired product.

One more thing, keeping the solution cold will increase the amount of NO2 that dissolves but since it is a reaction it might not work quickly at low temperature so there might be a trade-off there.

[Edited on 11/29/2004 by BromicAcid]

SAM4CH - 28-9-2006 at 02:54

What about solubility of NO2 in water at 25 Celsius and 1atm. pressure?

YT2095 - 28-9-2006 at 05:12

the water doesn`t HAVE TO to be at 25c though does it?
you can take it down to about 4c in a simple fridge :)

unless it Has to be 298k at 101Kpa (as in some homework questions)?

BromicAcid, the H2O2 idea does work quite well, pity you beat me to it :P

unionised - 28-9-2006 at 08:59

One other thing that didn't get a mention was to use lots of water.
Why are you doing this? If you just want to trap NOx rather than vent it to the atmosphere then the answer is different from that if you want to get a strong solution of NO2.