NNO2
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Nitric acid production by ammonia oxidation using electrolytic oxidation
Nitrogen oxide production using arc discharge consumes a large amount of electric power and produces only low-concentration products of about 1 vol%.
The Ostwald method using a cobalt oxide catalyst requires know-how for control such as feed control.
Also, these methods have the necessity of taking a large volume in the gas phase.
Therefore, we are considering whether we can obtain the object in liquid phase.
A kind person showed me how to use manganic acid.
The problem requires a large amount of reagents.
https://par.nsf.gov/servlets/purl/10057040
According to this paper, we found the possibility of achieving the objective by electrolytic oxidation with PbO2 anode.
Manganese oxide and cobalt oxide can also be used as anodes.
But they're stuck with papers and patents that say you can search for just nitrogen.
No mention of the desired response could be found.
Does anyone have any knowledge?
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Bezaleel
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The abstract says
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Graphite-supported a- and b-PbO2 electrodes (PbO2@G) were prepared by electrochemical deposition at appropriate potentials with regard to Pb(II)/PbO2
redox couple under alkaline and acidic conditions, respectively, for studying the direct electro-oxidation of ammonia in aqueous solutions. Results of
surface characterization including scanning electron microscopy (SEM), X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy (XPS) indicated
the presence of polymorphs of PbO2@G. Cyclic voltammetry (CV) of the electrolyte containing NH3 indicated mediation of electron transfer by PbO2. At
the onset potential of ca. +1.0 to +1.45V (vs. Hg/HgO), a pathway of NH3 oxidation to nitrogen byproducts, namely, N2, NO2- , and NO3- was proposed.
The removal efficiency and selective conversion of ammonia (0.1 M Na2SO4, pH 11, 25 C) on PbO2@G was determined based on controlled potential
experiments
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So they are using a graphite electrode with PbO2 deposited on it. I guess that it's key to their process or they would have taken some standard PbO2
electrode.
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Alkoholvergiftung
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Interesting Thing is when you Elektrolyse water it forms on the anode very small amouts of nitric Acid and on the Cathode it forms ammonia. An guy
named Nithack made an Elektrolyse apparete with Pt anodes and very small amounts of NH4OH as an electrolyte. He runs the cell under 50-100bar
pressur with air or Nitrogen.So he could produce Ammoniumnitrate. It was around 1898 and because of the use of electricity he wasnt cheap enough so
they forgott this Technologie.
Ive read some Australien Secentist try nowdays the same approch because they say it s CO2 neutral …..
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NNO2
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Thank you everyone for an answer.
The basic strategy is to secure sufficient yield in a limited space as soon as possible and to give up yield to some extent.
For example, by electrolytic oxidation in an aqueous solution of ammonium sulfate
We are exploring the possibility of a method to obtain sulfuric acid and nitric acid simultaneously and separate them by distillation.
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stamasd
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OP: note that the paper you linked to investigates the electrochemical oxidation of ammonia at very low concentrations, with the purpose of removing
it as a pollutant from water. It is not aimed at producing nitric acid at high concentrations. Essentially they don't care what the products are as
long as the ammonia is destroyed. Having worked myself with PbO2 and with manganese/cobalt oxide electrodes, I don't expect them to survive any
respectable concentration of nitric acid in the electrolyte. The Pb, Mn and Co nitrates are soluble and the electrodes will be corroded away. They may
survive at the 10mM concentrations that they use in the paper, but not at concentrations that may make this method viable for the production of HNO3.
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