Sciencemadness Discussion Board - Possibility of an easy O3/NOx generator

Possibility of an easy O3/NOx generator

Blind Angel - 23-1-2004 at 15:06

On a site for amateur experimentation with electricity and strange thing i found this:
How to build yourself a Glow Discharge Plasma panel

But what the link with the Subject of the thread? Well this sentence caught my attention:

Quote:

The surface layer of your OAUGDP device generates ozone and nitrogen oxydes, so you need to do these experiments in an open and well ventiled area

I think that this coul be quite usefull, no?

[Edited on 23-1-2004 by Blind Angel]

hodges - 24-1-2004 at 04:56

The circuit produces a high voltage using an automobile ignition coil. Any time you have a high voltage like this between two conductors that are spaced close together (in this case, the speaker wire), some sparking is going to occur, and thus some ozone and nitrogen oxides are going to be produced. The same is true with, for example, a Tesla coil. However, whether the amount of ozone and nitrogen oxides is increased by the panel over what would normally be expected when dealing with high voltages such as this, and whether it is enough to be useful for chemistry is a question I'm not sure of the answer to.

That is some weird stuff by the way. Thanks for pointing out the site.

Hodges

axehandle - 30-1-2004 at 20:45

What you're proposing was invented in 1905 (I think) and is called, I think, a Birkeland-Eyde reactor.

It makes nitric acid from electricity and air using lightning discharges. The reason it's not in use today is that the oxidation of ammonia method using a catalyst is more economical on an indistrial scale.

"By 1902 electric generators were in use at Niagara Falls, N.Y., to combine nitrogen and oxygen in the high temperatures of an electric arc. This venture failed commercially, but in 1904 Christian Birkeland and Samuel Eyde of Norway used an arc method in a small plant that was the forerunner of several larger, commercially successful plants that were built in Norway and other countries."

http://www.britannica.com/nobel/micro/426_74.html

Good news is that I'm building such a reactor, and will publish plans for it (yes, for free). It's not cheap though, the NST cost me about $200.

I made a prototype which had some serious design flaws that led to thermal stresses in the glass vessel i used (the electrodes get very hot) but before that it happily made nitric acid.

[Edited on 2004-1-31 by axehandle]

axehandle - 6-2-2004 at 11:37

Just 5 minutes more for the hot melt glue to cool, then I'm firing up the reactor!

30 minutes later: Another reactor vessel cracked. I'm gonna make a new one tonight, and this time the protruding parts of the electrodes will be watercooled! (Luckily I bought two water pumps recently.)

Fuck. I'm getting real tired of drilling glassware.

[Edited on 2004-2-6 by axehandle]

04:14 pm idea: Ah. Two clay pots, glued together using 180C proof silicon, electrodes held in a jacob's ladder stance by gypsum (dehydrated after curing), apparatus perforated by two 12mm copper tubes carrying a flow of coolant water. This will work. Must wait till 07 though, neighbors normally dislike hacksaw usage during sleep.

[Edited on 2004-2-9 by axehandle]

I'm making a web page to document my efforts so far. It might be of interest to others. It's not completely done yet, though.

http://species8472.dyndns.org/no2/no2.html

Comments, questions and flames are appreciated. Well, except perhaps the flames.

[Edited on 2004-2-12 by axehandle]

[Edited on 2004-2-12 by axehandle]

hotelyankee - 8-8-2005 at 17:46

I make ozone generators. The O3 gens are producing some nitric acid already. Im ozonating a textile water with a ph level of 12.5 and have managed to lower this to 9.6ph already. However, I'd still like to lower this to 8.0ph. Any suggestions on how i can increase the nitrous oxide production of my ozone gen?

By the way axehandle, I hope if you dont mind if I try to copy what youve done on your Birkeland design. Is it advisable to use a ceramic jar instead?

jpsmith123 - 11-8-2005 at 14:16

You're making ozone using a "silent discharge", i.e., a dielectric barrier discharge?

There's a U.S. patent that claims it's possible to make nitric oxide this way (sorry I don't have the number handy).

As I understand it, to make nitric oxide rather than ozone, you need more discharge power (a higher electron "temperature"

; which means either higher voltage, thinner dielectric (for increases capacitance), higher frequency, or a combination of the three.

Regards,
Joe

12AX7 - 11-8-2005 at 16:34

As *I* understand it..

O3 tends to be made by UV, which is made in quantity by low temperature (glow, spark or low power arcing) discharges in air. NOx however requires *heat*, to *fuse* the molecules together. A welder's arc would be perfect for this.

Tim

Ozonides

chloric1 - 11-8-2005 at 18:21

I remember reading along tme ago about alkali ozonides. These sound as if they would be terrifically powerful oxidizers. I can see it now, you have sodium ozonide at pH at about 13, and you bubble in chlorine dioxide to get the chlorate or even perchlorate!

Or dry sulfur dioxide instantly converted to smokin sulfur trioxide!

jpsmith123 - 12-8-2005 at 08:39

Don't forget that when you're talking about "heat" at the molecular or atomic level, you're talking about something different. Concepts that have meaning at the macroscopic level may not be a good description for what's happening on an atomic scale.

Anyway, according to what I've read in the literature, most of the NO comes from the interaction between atomic oxygen, and vibrationally excited nitrogen molecules.

I think you're right that arc welding would
make NO, but it seems to me that a properly designed DBD should do it also.

What I want to know is, what about an oxyhydrogen torch flame? What if you passed some air through an oxyhydrogen flame?

How hard would it be to make an oxyhydrogen torch that ran from a water electrolyzer?

Quote:

Originally posted by 12AX7
As *I* understand it..

Fleaker - 12-8-2005 at 14:52

I'm fairly certain NOx destroys ozone, hence the problem with nitrogen oxides destroying the ozone layer.

O3 is extremely unstable and very reactive, a dangerous material in concentration. Electric arc production of NOx is best done in a quartz tube. Ozone can be made and destroyed by UV radiation IIRC.

HNO3 from hydrogen flame

jpsmith123 - 16-12-2005 at 15:32

I happened to come across this interesting classroom demonstration which uses a hydrogen-air flame to demonstrate "acid rain" from HNO3.

I don't know how practical this method would be, compared to other methods, but I'm attaching the paper in case anyone is interested.

Quote:

Originally posted by jpsmith123
Don't forget that when you're talking about "heat" at the molecular or atomic level, you're talking about something different. Concepts that have meaning at the macroscopic level may not be a good description for what's happening on an atomic scale.

Anyway, according to what I've read in the literature, most of the NO comes from the interaction between atomic oxygen, and vibrationally excited nitrogen molecules.

I think you're right that arc welding would
make NO, but it seems to me that a properly designed DBD should do it also.

What I want to know is, what about an oxyhydrogen torch flame? What if you passed some air through an oxyhydrogen flame?

How hard would it be to make an oxyhydrogen torch that ran from a water electrolyzer?

Quote:

Originally posted by 12AX7
As *I* understand it..

Attachment: p1424.pdf (36kB)
This file has been downloaded 831 times

neutrino - 16-12-2005 at 19:37

I agree, this probably wouldn’t be practical for any significant quantities of nitric acid. A fascinating read nonetheless.

Mechaton - 6-5-2006 at 15:50

Ok, as soon as I get my Chlorate Cell put together, this is my next project. I have an old X-ray transformer that is begging to make HNO3 .