Using pH meter to adjust electrolyte mix?

[Lasse94]

Do you think it's possible to use a pH meter to correctly mix KOH/NaOH ratio?
It would have been quite easy to adjust right if you don't have an amp meter?
Thanks

[BioFarmer93]

Do you think it's possible to use a pH meter to correctly mix KOH/NaOH ratio?
It would have been quite easy to adjust right if you don't have an amp meter?
Thanks

Lasse,
Yes, it is possible, and some people do it that way. If you research this forum's archives you will find some references to the proper pH for a 28% KOH solution. The 28% solution is considered optimum because it passes the maximum current. You may use a stronger solution but there is no gain in production, and you will be wasting KOH.

[Bazarommcmullen]

Is the same 28% solution ideal for the Lye as well?

[Lasse94]

Thanks for answering guys! i thought i was the first one to try it though
is it 28 % for lye aswell?
Thanks!

[BioFarmer93]

Is the same 28% solution ideal for the Lye as well?

No. I think I remember it being around 20%, but I'm not sure...

[myoldyourgold]

Is the same 28% solution ideal for the Lye as well?

NO NaOH max is 20% over that things start going down hill. KOH is 28%

[Bazarommcmullen]

Is this measurement 20% by weight? I know I should search this site for previous discussion just thought I'd ask the question here while the topic is discussed.

[myoldyourgold]

Is this measurement 20% by weight? I know I should search this site for previous discussion just thought I'd ask the question here while the topic is discussed.

Yes it is by weight. It can be measured by a hydrometer. Cheap ones are used to measure the SG of battery acid. Here is a link for NoaH specific gravity by %

http://www.handymath.com/cgi-bin/nao...i?submit=Entry

[keiththevp]

I addressed this in another thread recently, you can not measure the concentration based off Ph. Do a test yourself with the cheap litmus paper tabs like I did. It only costs 5 dollars for the fish tank ones. Add a small amount of KOH or NaOH to water in one cup then add a lot in another cup, then test Ph, they will both be 13-14.

Now if you are talking about very small concentrations like an 1/8 of a tablespoon in a gallon of water then yes you can use Ph. But any reasonable amount added to actually make gas and no the Ph will always be 13-14

Myold is correct a hydrometer is the only accurate way to measure concentration.

[BioFarmer93]

Keith,
He asked about meters, not litmus paper. It may be erroneous to equate the measurement range and/or accuracy of litmus paper to that of an expensive lab grade piece of equipment.