Birkeland-Eyde process for making nitric acid

http://en.wikipedia.org/wiki/Birkeland%E2%80%93Eyde_process
My implementation of the Birkeland-Eyde process. This is my second system, I am runnung it for a week or so to verify the results of my first test, then I plan to add a pebble-bed plasma reactor to convert the NO2 to N2O5 and hopefully push the concentration above the 50% I attained last time.

Details and better description available at http://jennwork.homelinux.net

Category:

Science & Technology

Tags:

• Birkeland
• Eyde
• nitric
• acid

[summoningdark1]

@vmelkon you get visible NO2 after a couple of minutes. I let the system run for days/weeks to get the concentration in the bubbler up to ~50%

[cobrasniper555]

I have to ask again, what electrodes are you using?

[summoningdark1]

@cobrasniper555

They are Stainless steel rods with tungsten inserts. The tungsten comes from TIG welding rods.

[cobrasniper555]

On that note, what about making the air inside of the "vessel" oxygen rich with an oxygen generator/candle? That, along with instead of having the gas bubble through the water/H2O2 on the end, have it bubble into an upside down beaker inside of a larger container containing water/H2O2? I found that in other processes this will gather the gas and slowly allow as much of is to dissolve as possible, instead of just passing through.

[summoningdark1]

@cobrasniper555

Since only a few percent of the N2/O2 in the air is converted to NO2, the gas mixture in the system is already oxygen rich. I agree that a better absorption process is needed, quite a bit of NO2/NO escapes. right now the HV transformer is down with a carbon track internally that I need to fix, so progress is halted for the moment.

[packrat541]

I am using a solar panel to charge a 12 volt car battery that powers a two transistor occilator that outputs into a flyback TV tranformer and the high voltage dc is stored in a HV capacitor and discharges a high current spark in a chamber with water in the bottom with a piece of copper that stays bright and is producing a blue solution that forms crystals when evaporated that I think is copper nitrate and would also make a small amount of nitric acid if copper was absent. It runs 24/7 .

[gfx260]

I also have a video request.

Could you make a video demonstrating the concentration of this home made acid? it would be nice to see

[gfx260]

I have a question...

Is this process efficient or does it waste a lot of electricity for the person paying the power bill?

Also, how concentrated was the nitric acid that was made? could it be used for refining, or would it need distilling?

[hetrodinepallasoxide]

"I plan to add a pebble-bed plasma reactor to convert the NO2 to N2O5."

are you talking about re reacting the NO2 in another arc? in a ceramic honey comb? say a honey comb from the engine side of a catalytic converter. The rear portion of the converter is a NOx decomposing by design, and why? the answer is that the forward section generates NOx, in excess of the engine. might need to scrub COx though, to avoid side reactions of the CNy nature.

[Simlatio]

@Simlatio I'm also working on a reaction chamber using the most efficient design I can muster from the 6 well known flame furnace designs of old. Its not enough for me to just play, I hate spending money so when its constructed, if it turns out that its kwh is close or better yet lower than the 15000kwh per tonne of fixated N2, I may post it up if you are interested.

[Simlatio]

@hetrodinepallasoxide True, Hydro Norsk employed columns some 30 metres tall for surface area. And while bigger arcs are better, there is a diminishing returns concept here as American users of this process found. By using more air flow and a smaller arcing chamber, they increased yields greater than all other flame furnace designs. Also not sure how well your trickle tower will work as NO2 is a little fussy, it won't soak into NaOH solution through a gas dispersion tube well either.

[Simlatio]

@Tezcax Simpler systems do exist believe it or not.

[hetrodinepallasoxide]

an absorption colum is also needed for the acid production stage its about creating surface area.

[hetrodinepallasoxide]

i also thing this reaction would work better if a platinum catalyst 1 electrode was used

[hetrodinepallasoxide]

i read somewhere that it takes 900kwh of power per pound of produced product, 2 things, if the arc is more mobile and allowed to stretch to its maximum size like in a Jacobs ladder or is distributed from a fast rotary point to a outside ring the production is more efficient, and also just bubble the nox into water and allow the remaining gas to flow into a trickle tower of polyester fluff with potash solution with an excess of potash to scavenge the exhaust gas into a useful nitrate salts