RogueRose
International Hazard
Posts: 1594
Registered: 16-6-2014
Member Is Offline
|
|
Iron Oxide production via electrolysis - what electrolyte is best?
I'm going to try to make some Fe2O3 via electrolysis and I've seen videos and write ups that use NaCl or NaHCO3 and was wondering which would be best.
I would suspect that using salt might produce Cl2 gas though not sure. With the bicarb I would think that H2 would be produced.
As far as voltage, I can generate anything from 5v - 170v DC. If rust is desired and I'm basically looking for destructive electrolysis of the metal,
is there any reason not to to use a higher current density?
Setup is a 5 gallon bucket and I'm planning on using cast iron for the annode and cathode. Is there any reason to use something else for the cathode
like carbon/graphite plate?
Will this process produce any Fe3O4? I made some iron oxide with steel wool and bleach and got a mix of both Fe2O3 and Fe3O4 (maybe 6:1) but since
the hypochlorite is a strong oxidizer I think this may have something to do with the results.
|
|
|
Zyklon-A
International Hazard
Posts: 1547
Registered: 26-11-2013
Member Is Offline
Mood: Fluorine radical
|
|
I used bicarb and chloride (like 3/1) but I'm not sure how/if this is really better than anything else.
Iron (II, III) oxide can be made by passing water vapor over red hot iron fillings or steel wool.
|
|
|
ferrousexplosive
Harmless
Posts: 7
Registered: 3-7-2017
Member Is Offline
Mood: No Mood
|
|
I have done several pounds in the course of the past years, I personally don´t need the oxide in a great scale, i have almost always used sodium
chloride as electrolite, for the cell i use a 1 liter plastic jar and a 6v 0,5 amp current  idont really have another way to get more power than that. About chlorine production it happens, but only in small quantities even at
great scale, i recomend to have a inverted funnel and a hose to drive out and safely all the gases generated (Mainly hydrogen)
Sodium bicarbonate is good if you dont have anything else, however if you want a destructive process to completely disolve your anode i think it would
be interesting to apply constant heat to the solution, between 50-60 C to increase the conductivity, i used sodium hydroxide as electrolyte, the
result was the cathode producing oxygen and lowering greatly the production of iron hydroxide
|
|
|
Tellurium
Hazard to Self
Posts: 84
Registered: 12-7-2017
Location: Group 16, Chalcogen City
Member Is Offline
Mood: smelly
|
|
Wouldn't it be better to use an acidic electrolyte and then add some base to it after the electrolysis?
I always noticed, that the conductivity of Iron electrodes drop in basic medium, I think because of the oxide layer covering the surface area.
However if you use enough power to get a nice and strong gas production the oxide layer flakes of faster, so you wouldn't have that much of a problem
with it, but you're wasting power because of electrolysis of water.
|
|
|
ferrousexplosive
Harmless
Posts: 7
Registered: 3-7-2017
Member Is Offline
Mood: No Mood
|
|
I am relatively new to chemistry, it is posible to make electrolysis in acidic media without creating the salt of iron and the acid?
From my understanding, i would be created let´s say iron sulphate FeSO4 then you add the base like NaOH it wouls result Iron hydroxide and sodium
sulfate
FeSO4 + 2 NaOH → Fe(OH)2 + Na2SO4
right? the sodium salt would stay in solution while the iron hydroxide precipitates and can be filtered.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
