Sciencemadness Discussion Board

Can you grow crystals of iron through electrolysis as you can with tin?

John paul III - 17-4-2022 at 09:23

A few months ago nilered uploaded this video
It got me wondering, would it be possible to grow iron crystals this way? Or would they corrode as fast as they form?
Also, does the choice of electrodes matter (it isnt explained in the video), or can i use anything conductive?

Fantasma4500 - 17-4-2022 at 10:33

i believe rolls roys do this for some of their engines, growing their .. was it engine block or turbine fan or something? possibly for some type of aircraft, i find it hard to believe it wasnt infact some kind of alloy, possibly even stainless

if corrosion rates are the issue then it should be doable in basic medium, in which protects ferrous alloys- heard none about it yet though.

Plunkett - 18-4-2022 at 18:39

I made small iron dendrites (2-3 mm) once by electrolyzing a mixture of iron oxalate and iron sulfate, so I believe it is possible. The linked thesis found that a mixture of iron sulfate, ammonium sulfate, and ammonium oxalate gave good results for electroplating iron onto copper. Maybe start there.

[Edited on 4/19/2022 by Plunkett]

Fantasma4500 - 27-4-2022 at 06:13

well- im wrong.
page 10 from above posted link
"Acid Vs. Neutral Baths
It appears that slight acidity is beneficial,
at any rate in the case of the sulphate baths.
Slight acidity hinders oxidation of the solution,
and prevents the formation of basic salts at the
cathode. It, further, improves the conductivity,
and enables a considerably higher current density
to be employed without injury to, and frequently to
the benefit of, the depos it; but slight acid ity is
all that should be employed. If any considerable
quantity of free acid be present, the cathode efficiency
suffers in a marked manner; loss ofefficiencyis scarcely
noticeable with slight acidity."

"(a) F. Haber on Klein's Solution. This authority
states that he obtained faultless deposits from
Klein's bath under the following conditions:
Composition-.5g. mol. of MgSO4 sq. and the same
weight of FeSO4 sq. to each liter of water. Current
density-.25 amp./ Cathode--Lacquered sheet
(copper). He found that when he deposited the
iron tube(which served as anode), the deposit showed
a tendency to split up; but that if the cathode
cylinder was rotated, deposits up to .15 rom. thick
could be 0 bta med (and at the reletively high
current density of from .4 to .42
without any sign of peeling."

"K. Arndt states of the work 0 f Hoepfner and
Klie, "Dr. Klie has in 1895 deposited iron under
the following conditions: Bath-A weakly acid solution
of 462 grams FeSO4 plus 75 grams (NH4)2SO4
in 1.5 liters water. Cathode-Copper sheet, rubbed
with vaseline and sprinkled over with powdered
graphite. Anode-Cast iron plate. Diaphragm-Thin
porous plate inserted in a frame between the anode
and cathod e. The bath -temperature was maintained
at 700 to 800C. t the current density was about 3
amp./sq. dm., and the voltage amounted to .75 volt."

just the copper cathode with vaseline and graphite is something ive never heard of? the steel sponge produced is especially interesting as they state it reacts much more readily than zinc powder
zinc powder can take a long time to produce electrolytically, i spent days on just producing 10 grammes- likely because the base reacts with the zinc while its being formed, but electrolytic iron explains that theres very little oxidation- supposedly very little material lost to corrosion?

@plunkett what were the concentrations and pH of your experiment? approx amounts of iron oxalate and iron sulfate?