Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: dle on 05/10/2007 17:09:42

Title: Method for producing nitrogen dioxide
Post by: dle on 05/10/2007 17:09:42
Could someone please tell me the best method for producing nitrogen dioxide gas?

Thanx.
Title: Method for producing nitrogen dioxide
Post by: lightarrow on 05/10/2007 19:21:26
Quote from: dle on 05/10/2007 17:09:42
Could someone please tell me the best method for producing nitrogen dioxide gas?

Thanx.

Starting from what? Best in which sense? More rapid, or less expensive or more easy, or what?
If you look for an easy way:

8HNO3 + 3Cu --> 3Cu(NO3)2 + 2NO + 4H2O

then NO reacts immediately with O2 of air at room T forming NO2:

2NO + O2 --> 2NO2

Or, decomposing thermically lead nitrate:

Pb(NO3)2 --> heat --> PbO + 2NO2 + (1/2)O2

Industrially, NO it's produced oxidyzing NH3 with air on a PT-Rh net catalyzer at 800°C.

It's possible to make NO from N2 and O2 but it's more difficult: air have to pass through a voltaic arc at 2500-3000°C and then be cooled immediately under 500-600°C. In this way it's possible to get 6-8% of NO.
Title: Method for producing nitrogen dioxide
Post by: DrDick on 05/10/2007 20:37:22
Just drive your car around.   [;)]

Of course, if you wanted to COLLECT that gas, that's another story.

Dick
Title: Method for producing nitrogen dioxide
Post by: dle on 07/10/2007 13:33:28
Thank you.
Title: Method for producing nitrogen dioxide
Post by: lightarrow on 07/10/2007 13:39:33
Quote from: DrDick on 05/10/2007 20:37:22
Just drive your car around.   [;)]

Of course, if you wanted to COLLECT that gas, that's another story.

Dick
Good idea indeed! He should better use a diesel non-Euro4 car (and not an old kind). To collect it (not easy, as you say), he should make the gas pass through cold water or inside a very cold, long metal coil; NO2 will condense in liquid form (as colourless N2O4).