Edison
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Brine/Hypochlorite cell electrolysis
Hey all,
I am building an electrolytic cell to convert aqueous NaCl/brine into NaClO. I will be using a MMO anode with a titanium cathode. This will be the
first DIY hypochlorite cell I will be building, and could use some advice or references (I can't seem to find much material on DIY brine cells!).
I want to maximise yield of NaClO and not form any chlorates or perchlorates. Is there an optimum voltage or current that I should be aware of?
I was advised by the electrode's manufacturer that anything under 24V will be OK as far as the electrodes are concerned.
Thanks.
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macckone
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If you want chlorate free hypochlorite then you really need to generate chlorine gas and bubble it through cold sodium hydroxide solution. The
electrolysis method is not going to be chlorate free.
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j_sum1
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Question. Why don't you simply buy some laundry bleach if you want sodium hypochlorite?
Electrolysis seems like more effort than it is worth for something OTC.
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Edison
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Thanks guys.
Could you please recommend a reference book, paper, etc. that describes the conditions for forming hypochlorite, chlorite, chlorate and perchlorate?
@j_sum1:
True you can buy hypochlorite OTC but it isn't as fun as making it yourself 
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violet sin
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" True you can buy hypochlorite OTC but it isn't as fun as making it yourself
"
and it's freaking spendy!!! my pool eats cash like crazy, and I am also working on the same project right now.
so far I have rewound a microwave oven transformer(MOT) to make a spot welder. spot welded some MMO from Laserred ebay seller, to 1/8" Ti welding
wire, also off ebay, for electrode extensions beyond the cell. My initial run testing the weld went well. I used a smaller jam jar as my cell.
dissolved 3 -4 Tbs of salt from the pantry and hooked it up to a small electrolysis device I made previously. it was run at 4.5 - 5v and .27 - 1A for
at least 12 hours over the course of several days. it had to be stirred a few times before the current would pass, as noted with the .27A initial
conductivity. but it was running on average 0.75A
the salt water turned a nice bleachy yellow color and smelled like quite strong. no spot weld erosion was noticed, no flaking of MMO. the product was
sampled from time to time with a bamboo skewer, and tested on brown corrugated cardboard. this started as a decent tan color to a light straw yellow
to almost white. even if it did make chlorate, it worked.
I would also be quite interested in finding a way to maximize the output of my cell. there was little to go from in my searches. mostly a billion
people that have made chlorate cells and the rest were pool chlorination companies/installers. a couple Youtube vids, and some web sites( that I
didn't even bother bookmarking) came up, but weren't too insightful.
so far I have planned a larger 5gal bucket version for pool use. didn't want to have to pay an instillation guy/ adhere to building codes, so the
5gal works. no wiring in a special GFCI while keeping it proper distance from pool edge, or hacking my ancient plumbing open. we already buy 40lb
sacks of salt for the water softener, and I could make a batch as needed.
* I have worked a 13hr day today, so if any of the ^^^ was poorly worded/outlined, sorry.
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jock88
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http://www.sciencemadness.org/talk/files.php?pid=121766&...
Ullman's the dude
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Edison
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Thanks, very useful reading 
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