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/sci/ - Science & Math

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6023508 No.6023508 [Reply] [Original]

hey guys

im doing the electrolysis of water with a 20% KOH solution (potassium hydroxide). I want to make it as effective as possible for my uses.
How do i calculate the decomposition voltage (voltage needed that the electrolysis starts). i have been reading ranges of 1.2-1.7 V on the internet. but i'd like to know the exact formula with explanation.
the pressure is 1 bar and the electrodes are made of stainless steel and have a surface of 80cm^2
question 2: does voltage (other than decomposition voltage) play any rule in the electrolysis of water or do you only want to have as much ampere (current) as possible

pic unrelated

>> No.6023547

bump

>> No.6023557

why the fuck are you using stainless steel?

>> No.6023573

>>6023557
platinum is too expensive?
why, is it bad?

>> No.6023581

>want to oxidize anode
>use hard to oxidize iron

>> No.6023584

>>6023581
i dont want to oxidize the anode
the goal of this is to produce hydrogen

>> No.6023628

bump

>> No.6023630

>>6023573
use copper and tin

>> No.6023648

>>6023630
why is stainless steel bad?
next time i will take copper on hydrogen and tin on oxygen side, thanks for the tip
because of toxity? its not like im going to drink it anyways..?

btw can somebody explain me the voltage potential?
here's the nernst equation
E=E0+0,06Vz⋅log[Ox][Red]
can somebody explain it to me with the use of KOH (aq) and SS electrodes?

>> No.6023736

bump
captcha toxicity cperiod

>> No.6023972

bump

>> No.6024244

>>6023508
just run a cyclic voltametry experiment

>> No.6024264

>>6023648
steel is designed for strength.
It's electrical properties kinda suck

>> No.6024270

>>6023648
Also I'm pretty sure that you might get some nasty hydrogen embrittlement.

>> No.6024790

bump

>> No.6024796

>>6024270
not for steel at such low H2 pressures. Read API RP 571 for example.

>> No.6024800

>>6024796
ahh i was thinking that the electricity somehow let the protons fuck up the structure.
I mean that's why you don't want to weld in the rain right?