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making potassium (per) chlorate


gods knight

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I know this thread is immortal in the sense that noobs arrive, get interested, and kick it back up. I guess it's my turn.

 

The anode is the obvious gotcha, and has been flogged to death. Has anyone tried 24K gold wire? I have a small spool left over from some hand engraving inlay, and I was curious to see if it would work without erosion. No one wants to give up $800/ounce Au into an irrecoverable solution.

 

In particular, I am interested in KClO3 production. I know I can buy it... I just enjoy the challenge, I guess. KClO4 will come later.

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Well, problem with graphite electrodes is that damn corroding of the anodes, but i've been successful in using them in a small drinking-glass sized cell.

 

10 g. of NaCl and 140 g. of water was used in combination with 3 graphite electrodes and the metal soupcan as the cathode.

 

Pretty much ignored the corrosion and went full throttle with the battery charger and used rigorous cooling (Snowslush in a bowl, this was in the winter). 36 hours latrer:

 

Anodes almost completely gone, a black goo in the soupcan.

 

Filtered the black goo out (most of it anyway) and let the water evapourate, and voila! The dried filter paper with the goo pretty much went *voff* from being soked and dried in the chlorate solution.

 

Ph control: a tablespoon of 30% HCl just towards the end, two hours from being finished.

 

Now this batch is still waiting for a use. Ill just have to get off my butt and get things done!

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One of the reasons I want to get a bit more familiar with this process (transformation of NaCL and KCl into chlorates and perchlorates) is that I can see the day coming, perhaps, when oxidizers are VERY much more restricted than they are now.

 

When that day comes, KClO3 and KClO4 will be easier to make than KNO3, I think. If you can make perchlorate, you can do just about anything pyrotechnically that you need to do.

 

SAD NOTE, and suggestions needed, please - I let the magic smoke out of my faithful power supply. It was a 0 to 15V, 0 to 30 amp job, a really nice supply I used for everything from charging batteries, to anodizing, plating, etc. What sort of power supplies are you guys using for these cells, and what sort of currents are you seeing, for a larger cell capable of real production, as in kilogram production, not benchtop gram stuff?

 

Switching power supplies are out. I'm thinking a bit of a ghetto setup would be a 6V lead-acid battery, with a battery charger connected to it so as to continually keep the charge up. Trying to use a modern switching charger in a cell probably will not work.

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I use a PC PSU - the 5v lines will deliver big chunky amps on most newer units, so will the 3.3v lines, depending on how much juice your anode can handle.

 

I should mess around with the anodes a bit more soon, just gotta find the time... and take all my crap over to the in-laws to do it outside...

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Swede - Sounds like a very nice supply, is it transformer or switchmode based? I would definatly pull it apart and get it fixed, a power supply like that will be very expensive to replace (I have something similar (3-15v @25A) and it would cost me $350 to get it replaced)

 

I use a old ATX power supply as they work well, I am limited to around 10A. If you want bigger your best bet is to rewind a MOT (microwave oven transformer).

 

My large cell is just sitting in the garage with about 2" of chlorate crystals in the bottom, I might give it to a mate to use. Stay away from graphite, just spend the $30 and get a MMO anode.

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I've got the good electrode set coming, and a spare set to boot. I played a bit with 316 stainless steel. I knew it wouldn't work, but I did want to see what we're dealing with here. It was eye-watering, the erosion at the anode was spectacular, and within 1 hour, the 316 stainless wire had dissolved at the junction of anode to electrolyte. A thick scum of ferrous goo formed on the surface. I have a lot of respect for the home pioneer types who worked so hard investigating anodes. With the MMO anodes now available, problem solved, with a few $$.

 

WarezWally, the supply was an analog linear PS, pretty low-tech but effective. It did not have CV/CC (constant voltage/constant current) functions like a better lab supply, but it made up for it with brute power.

 

I opened it up - the regulation part of the board was charred, and dead. The MOSFET's or whatever they are may, or may not, be still good. It has a monster transformer. I'll hang onto it and make it a project for later, but I think I'm going to invest in a 20 amp lab supply with CC capability. I need that for anodizing and plating as well, so it'll be an all-around supply. You guys are right, big $$, probably about $400.

 

Goal - kilograms of perchlorates, to be stored for a rainy day! :P I love electrochemistry, purification, recrystallization, and the ultimate goal of making a chlorate-free product. That is going to require some of the sensitive tests published at various sites. Fun!

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My chlorate production has gone at a dead standstill and wont possibly start again for the next few days...

My brother had recently taken an interest in pyrotechnics and has started constantly bothered me on how to make fireworks. It so happens that he found out about my Perc cell and, in blind anger for me refusing to let him use my chemicals, he took my Pl anode cell and tossed it into the backyard pond. :angry:

 

 

He unfurtunatly he hadnt realised what he had done.

I tried to recover what I could but I could only find the plastic jar.

:(

 

90.00$ worth of Pl and titanium gone, with only so much as an apology from the brother! :angry:

 

I've basically gone back to begging my parents for money for a new cell -_-

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Sheesh....

 

Tell him he's lucky he isn't my brother.

 

I'd have peeled his ass off in strips,

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It'll be time to worry when the catfish start making perc. You'll drop a line in the water, feel a tug, and reel in a 50g salute. ^_^

 

I'd say get his rear out there in the water with a mask and snorkel. Wow, that's annoying of him.

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I have a feeling that dumping the cell in the pond has had the effect of raising the pH and killing everything.
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It so happens that i did find a few dead fish this morning and my parents are a little concerned about their pond, anyone mind sharing somthing that may delude the chlorate?

 

 

 

 

As for the link on the Ceramic LD ANODE Dcberry posted I might try making a few , seeing as I have no CHLORATE CELLS! to worry about!

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  • 5 weeks later...

I never do 1-phrase replies... usually, I write a novel! ^_^

 

I've been making and stockpiling KClO3 on my way to KClO4. I've read pretty much every reference to chlorate cells that I could get my hands on. I'm using an MMO anode, and the crystals seem quite clean.

 

my question - somewhere (I thought it was Wouter) I read that at 10% by weight (100g/l) chloride ion concentration, a cell will begin to manufacture perchlorate. If the chloride concentration continues to drop, the stresses on the anode increase, with failure a possibility. A MMO anode is not suitable to make perchlorates directly, thus I have been stopping the cell production when the Cl- is at 10%. But the starting liquor is only about 14% chloride ion, even heavily saturated it starts at maybe 17%. So I'm going from only 15% down to 10%, a pretty small range.

 

Did I misread the so-called 10% rule? I could easily double the yield by proceeding down to 6% chloride, but I don't want to hurt my anode. If anyone is knowledgeable about this, I would appreciate some help. Heck maybe I'll simply drive it to 5% or 6% and see if the anode can hack it. If so, it would be a boon.

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I believe what they mean is 10% of the saturated concentration - as you can't achieve a true 10% solution with some chloride salts and they can be electrolyzed.
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I believe what they mean is 10% of the saturated concentration - as you can't achieve a true 10% solution with some chloride salts and they can be electrolyzed.

 

If there was a head-slap :mellow: I'd use it. That does make sense. I could not see a chlorate cell shifting to perchlorate to any degree with a whopping 10% chloride ion by weight remaining when you start with only 15 or 16. I CAN see the reaction proceeding to perchlorate when you go from 15% to 1.5% by weight chloride ion.

 

There are now three ways I can think of to monitor the progress of a chlorate cell. The first is with any chloride quantitative measurement, the titration strips being the easiest. The second is with a qualitative/quantitative test for perchlorate. Pick one that is not super-sensitive, as there will obviously always be some perchlorate ion in small concentration from the beginning.

 

The final method is easiest with a power supply that is capable of Constant Current (CC) operation. At the start, set the current to an acceptable level, say 20 amps, and leave it there. Note the voltage required to create 20 amps of current. It will be at its lowest with high Cl- concentration. As the reaction proceeds, the voltage requirement will increase, probably noticeably, as the cell shifts to major perchlorate production. Much like temperatures in a distillation, although probably nowhere near as crisp. The electrolyte level must be consistent for this observation.

 

Using any/all means to detect perchlorate, with all else being equal, by noting the voltage at that point, I would guess that you could be very consistent batch to batch at the point to halt the electrolysis.

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So, ive been reading this for about an hour, and this has encouraged me to give production a try.

 

I have a battery charger capable of 50 amps and it runs at 12 volts. it is also cabable of 2 amps, and also 20 amps.

 

what setting should i be using?

 

and can someone please recommend an anthoide/cathode that i can use, preferably found at a hardware store. (i really don't have 90$ to be spending on platinum)

 

Thanks.

Edited by PyroMedia
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