How pure needs KOH/NAHO be 85-100% ?

[jwhhopower1978]

I order some real pure KOH 99%+ PA lab grade quality, but it was quait expensive 1kg * 4 = 4kg for 180$ (calculated from SEK) to me and some friends..

Can it be unnecessaray high quality ?

I also find from our hardware store/autopart shop, Sodium hydroxide (NaOH) lye/caustic soda, and on that can it describe that its 85-100% (guess its not near 100% more like 90%) pure NAHO, Do you think it´s good enough ?

What kind is quality standard KOH, NAHO do you guys use ?
(you how has hod systems up and running for years now)

[lhazleton]

You get what you pay for. Most of us use NaOH for conditioning only. If you can get 99% KOH, USE IT! I've always used 92%, as it's the best I've been able to come across.
The problem with NaOH sold in stores is "what makes up the other 15%"?
Since it's usually drain cleaner, it may contain aluminum and other metals (if it's the crystal form).

[Stevo]

I order some real pure KOH 99%+ PA lab grade quality, but it was quait expensive 1kg * 4 = 4kg for 180$ (calculated from SEK) to me and some friends..

Can it be unnecessaray high quality ?

I also find from our hardware store/autopart shop, Sodium hydroxide (NaOH) lye/caustic soda, and on that can it describe that its 85-100% (guess its not near 100% more like 90%) pure NAHO, Do you think it´s good enough ?

What kind is quality standard KOH, NAHO do you guys use ?
(you how has hod systems up and running for years now)

Most of us choose to use stainless steel because it is the most cost effective solution, but it has been proven that nickel is superior (unless you subscribe to the BB school of thought). For the same reason, most of us use ~90% KOH which is available readily and for a very reasonable price in most cases. Probably the best thing you could do is try to find the highest purity of KOH for your budget and use pure deionized water ($0.39 / gal.) versus distilled water.

[jwhhopower1978]

You get what you pay for. Most of us use NaOH for conditioning only. If you can get 99% KOH, USE IT! I've always used 92%, as it's the best I've been able to come across.
The problem with NaOH sold in stores is "what makes up the other 15%"?
Since it's usually drain cleaner, it may contain aluminum and other metals (if it's the crystal form).

ye your right, whats the other 15% in cheaper NAHO..

Thanks for the advice..

My lab grade 99% KOH arrives on monday, and I can finaly start condition my system and soontest for MMW.

[lhazleton]

I forgot to mention that with KOH, the only difference in the purity percentage is distilled water. In other words, the only thing that can be affected by different KOH % is the amount required to bring the electrolyte to the desired potency.