NaOH vs KOH

[BoyntonStu]

I found this on another forum.

Koh will dissolve 7% more by weight in water, and when used at the
highest concentrations possible, it is less resistive, it becomes more
efficient than Naoh, if you have a high end efficient sealed series
cell, you would max the Koh and control with a pwm, if you have an
open bath type, max concentrations of 28% by weight are not possible,
Naoh becomes just as good at lower levels and is easy to get,
cleansing and conditioning the plates for better production, must be
done with Naoh, having a higher boiling point for the job.

Do you agree?

BoyntonStu

[Haywire Haywood]

I looked all over for potassium hydroxide and all I found was the Sodium so that is what I ended up buying. I doubt I'll be running heavy concentrations so it should be fine. I've got another set of plates drawn up, hopefully will be cutting them out and testing them today.

Ian

[BoyntonStu]

I looked all over for potassium hydroxide and all I found was the Sodium so that is what I ended up buying. I doubt I'll be running heavy concentrations so it should be fine. I've got another set of plates drawn up, hopefully will be cutting them out and testing them today.

Ian


Ian,

I hope that this helps.

BoyntonStu

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[justaguy]

I first tested my generator using sodium hydroxide in my nephews shop because i,d forgot to bring my KOH with me. We started out with 1/2 tsp and was pulling close to 30 amps and climbing fast.

I poured it out and started again with 1/4 tsp. was pulling about 12 amps and climbing, also only putting out .5 lpm and heating up. I added a pinch to make it 3/8 tsp. went past 20 amps still only .5 lpm. After about 10 minutes was nearing 30 amps again so I decided to abandon the test with sodium hydroxide.

Later I do the test with KOH, I added 1/4 tsp. amps are at 12. I let it run several minutes and the amps never change. I add another 1/4 tsp making it 1/2 tsp amps go to 22. I let it run again several minutes and the amps never change.

I add another 1/4 tsp making it now 3/4 tsp of KOH. The amps are at 27. I let it run a while , amps stay at 27 so I decide to do a lpm test. I am now getting 1lpm. I leave it running for quite a while and the amps top out at 28 and much cooler than with the sodium hydroxide.

I know a lot of people use the sodium hydroxide but the amps and heat ran away big time with my cell. The hho was half too. I was sure proud to see how stable my cell was with the KOH. I,m going to try to install it on my truck hopefully this week.

[BoyntonStu]

I first tested my generator using sodium hydroxide in my nephews shop because i,d forgot to bring my KOH with me. We started out with 1/2 tsp and was pulling close to 30 amps and climbing fast.

I poured it out and started again with 1/4 tsp. was pulling about 12 amps and climbing, also only putting out .5 lpm and heating up. I added a pinch to make it 3/8 tsp. went past 20 amps still only .5 lpm. After about 10 minutes was nearing 30 amps again so I decided to abandon the test with sodium hydroxide.

Later I do the test with KOH, I added 1/4 tsp. amps are at 12. I let it run several minutes and the amps never change. I add another 1/4 tsp making it 1/2 tsp amps go to 22. I let it run again several minutes and the amps never change.

I add another 1/4 tsp making it now 3/4 tsp of KOH. The amps are at 27. I let it run a while , amps stay at 27 so I decide to do a lpm test. I am now getting 1lpm. I leave it running for quite a while and the amps top out at 28 and much cooler than with the sodium hydroxide.

I know a lot of people use the sodium hydroxide but the amps and heat ran away big time with my cell. The hho was half too. I was sure proud to see how stable my cell was with the KOH. I,m going to try to install it on my truck hopefully this week.

Good post!

Thanks,

BoyntonStu

[Haywire Haywood]

I doubt I'll be running heavy concentrations.

Famous last words... I had 3 +-+ cells in series hooked up to 6v today and had to use 2 rounded tsp in a quart of room temp distilled water to get 6 amps.

Ian

[1973dodger]

BoyntonStu,

Very interesting thread, I have had suspections that many people have assumed the 28% max. concentrations applied to all electrolites, when it only applies to koh. From what experiment I have done, lye will not increase current after a point, which is much lower than the mentioned 28%.

1973dodger

[timetowinarace]

I first tested my generator using sodium hydroxide in my nephews shop because i,d forgot to bring my KOH with me. We started out with 1/2 tsp and was pulling close to 30 amps and climbing fast.

I poured it out and started again with 1/4 tsp. was pulling about 12 amps and climbing, also only putting out .5 lpm and heating up. I added a pinch to make it 3/8 tsp. went past 20 amps still only .5 lpm. After about 10 minutes was nearing 30 amps again so I decided to abandon the test with sodium hydroxide.

Later I do the test with KOH, I added 1/4 tsp. amps are at 12. I let it run several minutes and the amps never change. I add another 1/4 tsp making it 1/2 tsp amps go to 22. I let it run again several minutes and the amps never change.

I add another 1/4 tsp making it now 3/4 tsp of KOH. The amps are at 27. I let it run a while , amps stay at 27 so I decide to do a lpm test. I am now getting 1lpm. I leave it running for quite a while and the amps top out at 28 and much cooler than with the sodium hydroxide.

I know a lot of people use the sodium hydroxide but the amps and heat ran away big time with my cell. The hho was half too. I was sure proud to see how stable my cell was with the KOH. I,m going to try to install it on my truck hopefully this week.

Wondering if your plates were conditioned before this test?

I know every time I've used new plates or had handled used plates my current always increases as the plates conditioned and production was low. Once this is done, the current has always been stable and production increased.

[justaguy]

Wondering if your plates were conditioned before this test?

I know every time I've used new plates or had handled used plates my current always increases as the plates conditioned and production was low. Once this is done, the current has always been stable and production increased.

Yeah, I did take that into consideration also. I,m not taking a chance trying sodium hydroxide anymore though, some say sodium will contaminate the cells. I do know the KOH was very stable in the test. I think i,ll run a couple more test later with the KOH . With such low measurements i,ll almost have to use tweezers and put the flakes in one at a time to get the exact amps I want, but at least they are staying there.

[bigapple]

BoyntonStu,

Very interesting thread, I have had suspections that many people have assumed the 28% max. concentrations applied to all electrolites, when it only applies to koh. From what experiment I have done, lye will not increase current after a point, which is much lower than the mentioned 28%.

1973dodger

also know that when temperature increases and pressure increases, u can add even more electrolyte and make a supersaturated solution if it gets hotter, not that it will effect the current after a certain point anyway. but with the temps we're running in cells, supersaturation wouldnt be hard to obtain but mite also cause thermal-runaway. a double-edged sword i guess

[1973dodger]

Yeah, I did take that into consideration also. I,m not taking a chance trying sodium hydroxide anymore though, some say sodium will contaminate the cells. I do know the KOH was very stable in the test. I think i,ll run a couple more test later with the KOH . With such low measurements i,ll almost have to use tweezers and put the flakes in one at a time to get the exact amps I want, but at least they are staying there.

Just wondering, if koh is this powerful, why would you need anywhere close to a 28% concentration. You have my curiosity up concerning koh.

1973dodger

[bigapple]

Just wondering, if koh is this powerful, why would you need anywhere close to a 28% concentration. You have my curiosity up concerning koh.

1973dodger

i guess thats the whole issue with it here. since such a small amount is needed to draw so much amperage and increase production, why would u need more?

[justaguy]

Just wondering, if koh is this powerful, why would you need anywhere close to a 28% concentration. You have my curiosity up concerning koh.

1973dodger

Yeah dodger, my thoughts exactly about the 28%. If I used that much my cells would blow up, lol. My plates are 1/16 two cells hooked in series. I,m serious, my last test I started out with one large flake of koh. Then I went to 1/4 tsp at a time until I stopped at 3/4 tsp.

I have read about several others doing the same thing then again read about someone using 2 tsp of koh. I don,t have an answer for that other than the cell. Some say the cells are really picky. I guess this explains why you can build two that you think are exactly alike and get different results .

[eloid]

KOH- Potassium Hydroxide in canada ontario

[bigjim56]

I believe the 28% is a "sub zero freeze point" . I know its not needed now because of the spring/summer temps. Stu had listed a freeze point graph a few months back that at 28% a solution of KI/DI will not freeze until it gets to like -62 F. Don't quote me on the exact temp here, going from memory.

Also with the 28% solution, when used in conjuction with a PWM it will give immediate HHO production upon start up rather than having to wait a few minutes to really start producing quality HHO. I think we all know that as the dry cell runs it gets warmer and more productive (amp/current usage climbs also). With the 28% electrolite, all of this happens immediately upon start up.
It is a good way to increase efficiency for people with short 15-20 min. drives, rather than 40-45 min.

The problem here is to get to 28% KOH it was projected to use an astronomical amount of KOH (almost 10 lbs/gallon DI!). So you've got a very valuable solution there, not to mention extremely caustic. For now I'm using a lower strength KOH/DI solution, but by winter it will be closer to the 28% to get through the winter months. Around the midwest we RARELY see temps. at 0 or below, so the 28% is overkill IMO.

eloid, I answered your KOH on the other thread. Nebraskabiopro.com is where I get mine, he sells from his website and off ebay.

bigjim56