What Went Wrong in My Attempt to Make Potassium Chlorate?

[mrjeffy321]

Well, I still don't have any pyrex yet, but I did boil down a lot of bleach and make another attemp at chlorate.
this experiment took place over about 2 weeks, so I don't really remember any more the exact amounts of everything I used any more, but I think I was around 1 liter of bleach (which I boiled down to around 600), and a bunch of potassium chloride.

I haven't finished it yet, I haven't filtered out the stuff at the bottom and dried it out, but here is the interesting part, I have this concentrated bleach solution, I boil that and add a bunch a potassium chloride, mix it up thoughouly,...wait, cool it down in my refrigerator for 2 days and see what percipitates, nothing!, not exactly nothing, but the only thing that percipitated was a coupld little impurity particles things that passed through the filter I used right after I boiled it, so I decide the filter that out and putit back in the refrigerator for another day, so I do.
the next day what do I see? a bunch a white granuals (and crystal looking things) at the bottom of the bottle, mind you all I did to it was filter it once to remove those tiny little umpurites, nothing else, it didnt even warm up very much while filtering it.
so now I potentially have some chlorate, and probably chloride, at the bottom of my bottle, why is it just not getting around to percipitating out, why not yesterday, or the day before?

 

[pack_rat2]

...o now I potentially have some chlorate, and probably chloride, at the bottom of my bottle, why is it just not getting around to percipitating out, why not yesterday, or the day before?

I don't think there's any KCl, since it's too soluble. I think maybe it cooled down more, the second time, but I'm not sure.

 

[Dinner]

I am trying to make sodium chlorate (don't ask me why) by electrolysing a solution of table salt. I'm using a graphite anode and a stainless steel cathode. When I start electrolysing the solution an orange-brown precipitate forms (much like MrJeffy's). I looked at the ingredients of the salt I was using and it had Potassium Iodide in it! This, I think, would produce triiodide ions (and then iodine?) and is probably what causes the precipitate. Will this affect the formation of chlorate ions?

 

[mrjeffy321]

well the percipitate I got when trying to make chlorate through electrolysis was white, and I think we semi-determined that it was due to the impurities in the water (like floride, ...) and then it stopped occurring once all that stuff was used up and the water remained relativly clear.


for your table salt (mostly NaCl), there is indeed some potassium Iodide (KI) in it, but hardly any, I mean something around the order of .002% by wieght I think. so if you had a hypothetical amount of let's say 100 grams of salt dissolved in water, you would only have .2 grams of KI, and that is only about .0012 moles. so this is really, not very significant, not to say that it couldn't indeed be the cause of your problem, but I doubt that it is. plus, iodine/iodide compounds (at least the ones I know) are usually dark purple/blue/back, not orange-brown.


since you are using a stainless steel electrode (cathode) I am inclined to think that that is the cause of the percipitate, even though it is the cathode, it will corode slightly, but not nearly as much as the anode might.
I try to steer away from using any type of Iron (which includes(stainless)steel) in my electrolytic cells, it never ends well for the electrode.

try it with a graphite cathode as well as a graphite anode, and see if there is still some percipitate, also try using disstiled water insted of tap water if you arent allready doing that.

 

[mrjeffy321]

just an update on the status of that last batch of hlorate.

I had high hopes for this bacth, and it looked as if I was going to get a lot (comparitively) this time, and when I dried it out, it looked good. but when I tested it...
yellow (and slight, barely noticcible green) flame, the tale tell sign of sodium chlorate. Not that I don't like sodium chlorate, but it is just not what I am trying to make, especially after I add al that potassium chloride to the mix, and then nothing happens. I really need to get some pyrex I suppose to try this.


speaking of pyrex, I was at the store today looking at some pyrex cups I could use, and they say specifically on them, "not to be used on stove top, breakage may occur". it this warning just for stupid people who try to heat up an empty cup over an open flame, or should I actually follow this because it will break if I try to boil bleach in it, I think it is the former, right?

 

[pack_rat2]

First of all, I should point out that the slightest trace of sodium ions will cause a yellow flame, and it will mask the violet of the potassium. Second, you say "green"...hmmm. I think that's from free chlorine gas that comes from undecomposed hypochlorite. What you have can't be NaClO3 if it precipitates out from any significant volume of water. NaClO3 is EXTREMELY soluble.

 

[mrjeffy321]

so your saying, the sodium will easily cover up the potassium color, even if I just have a little.
which makes that previous instance of the violet burning powder potassium chlorate all the more special because it must be very pure.

there is just a little green, the vast majority of the color yellow.

acording to MSDS, NaOCl solution is "100 % solubile in water", but that doesn't mean that when the water is evaporating off the crystals in the filter, some isn't left behind, although it is odd that there still would be NaOCl left, after all that boiling and reacting.

I was experimenting with containers I could boil my stuff in, I tried an aluminum soda can, and it worked surpisingly well, considering its very small surface area in contact with the stove. it didnt corode, although the thnk plastic film coating the inside did come off.

 

[pack_rat2]

I was experimenting with containers I could boil my stuff in, I tried an aluminum soda can...

Just be aware that NaOCl is a strong base, and bases react with Al to form aluminates, with the evolution of H2. If no gas bubbles form, you're OK. Those cans often have an invisible plastic coating which protects the surface.

 

[mrjeffy321]

and bases react with Al to form aluminates, with the evolution of H2.

O really, I didnt know that, cool, I learned something new today.

If no gas bubbles form, you're OK.

well no, hydrogen gas bubbles formed (that I know of), but hopefully a lot of steam gas bubbles formed, hard to tell what it was, but the only danger I see of making hydrogen gas is the possibility of it combusting, and this isn't likely with the tiny amount I might have made.

Those cans often have an invisible plastic coating which protects the surface.

these do, although I think, not sure, that some of the coating came off while boiling, because it was bubling up from the can with all the gas forming around it, but I can't find any peices of it now.


I cooled that stuff down, and WOW, I got a lot of crystals, filtered then and put it back into the refrigerator, and checked again, WOW, another large second batch, so I filtered those. they are still drying, so no word on how it will come out yet. but I don't think I want to use aluminum cans any more, for the reasons you said, but also because it can hold very much liquid and it had vertually no contacting surface area with the stove, so it takes forever to heat up, and a high center of gravity, as conpared to a pot for example (spills waiting to happen, not something I need). and I am now werry of using pryrex on the stove (because of its warning label descibed above), are there diferent grades/strengths of pyrex? some mroe suited for my purposes/laboratory pruposes?

 

[mrjeffy321]

A coffee pot seems to work for a pyrex substitute, if it isn't already pyrex (it doesn't say), i boiled a lot of liquids in it, and I got a lot of crystals, but I think the stuff I am getting now is less pure than what i was getting before.
the crystals are harder and don't crush into as fine of a powder as they once did, and it is harder to light.
I am probably boiling away too much liquid, so that the salts cannot dissolve and percipitate out too, that is what I am thinking.

 

[pack_rat2]

Remember that NaClO3, which is what you're making by the decomposition of NaOCl, is very soluble. So is KCl. When you add the KCl sol'n to the NaClO3 sol'n, the relatively insoluble KClO3 precipitates out. You want the initial NaClO3 and KCl solutions to be as concentrated as possible (though not super-saturated).

 

[mrjeffy321]

I seem to be getting very good at making a chlorate that burns yellow now, I can make batches of around 10-15 grams at a time of a fine white powerder that burns yellow (and just a slight tint of green).

With another two batches under my belt that work as described above, I am really getting good at this, with less than compleate satifaction.
It is obviously not pure enough (or the right type) to burn the correct color, and it is rather time and space consuming to make it. Also, as a matter of interest, i took a quick trip out to the power meter outside and checked to see how significant a dent in the electric bill my electric stove is making now that it is running much much more than it is ever used, and a surprizingly fast and noticable change in the spin of the dial.


What about this as a way of purifying the product, set the crushed powder in a finter and slowly pour a small amount of cold water over it (volume of wate varies with amount of chlorate), the cold water won't dissolve much chlorate, in theory, and should remove the sodium, chlorine, ... impurities that is present.
This idea is similar to the suggested process that was given in the instruction of making the chlorate, but I am afraid of loosing to much in the process due to it dissolving away, despite its low solubility.

 

[Sparkee]

chlorate production

Hi,new member here! I have had some success with chlorate production by electrolysis using an old computer supply and carbon arc rods. Most of the information I gleened from the web. Visser's site being one of them,another site was rouge science(no longer available?) The power supply, the amount of solution, how many rods,etc... all were contributing factors. To the amount and how long it took to process. Not to mention that once you obtain the NaCLO3?? a double replacement reaction is necessary to obtain KCLO3. One of the test I used was combining the dryed KCLO3 with powdered sugar and adding a small amount of H2SO4. If you get a reaction the concentration is supposed to be above 20%Caution! It will happen fast! In your face fast if proper care is not taken! If I can be of help let me know. If the Chemistry is wrog please excuse me as I'am an Electrican not a chemist.

 

[mrjeffy321]

Hi, glad you decided to contribute to my thread.
you probably haven't read all my prior posts on this subject, but I did try the electrolysis method once, but I became very discurages with it due to the long hours of just waiting for it, ..., then I started having problems with the current jumping from high to low and then nothing at all, then I burned out some power supplies and ruined some batteries, and to top it off, I spilled the jar loosing half the solution! I had some really bad luck, and I didnt like just wasting all that hydrogen (I used to make and collect a lot of hydrogen a few months ago for some hydrogen detenations and for my fuel cell I buil, before I upgraded to some real explosives), and I also has problems with the (graphite) electrodes and the wires attatched to them clouding up my solution.
but it is nice to know that, with a little luck, other people seem to have great success with it.
One nice thing I found was a program on the internet that would save me a lot of time a guess work, insted of me working out how much salt, ... how long to run the cell, ..., you just input your starting conditions into the program, and it will compute it for you.
I do want to go back to the electrolysis method again, that is the more efficient and less labor intensive way of doing it(and cheaper), but I am currently out of supplies to do it with, I burnt out my last good power supply I can afford to loose, I still need to work out a better method for the electrodes, and Idealy for easily capturing the hydrogen gas (but that isn't necesary, just something that would be nice), and I need a way to measure the current, I have a multimeter but it wil only go up to 200 mA, I don't want to wait that long so I prefer full amps when I do it, I borrowed a ammeter from school and I kept that for a long time so I don't want to impose on them again to borrow something, especially now that they will be using it soon.


Tell me, were you very successful making chlorate, how much did you make? in how big of batches? any other advice?

I'am an Electrican not a chemist.

well, I fancy myself a physicist before a chemist, not that I am an expert at that either.

 

[Sparkee]

chlorate production

I used a 2 Gallon container, 1600g of NaCL in a saturated solution,8 carbon arc rods that were connected with magnet wire to the cathode,some stainless steel hard ware for an anode. the power supply was one that I picked up at a discount computer store for $10.00. I ran it at 5v and 6 A for 300 Ah keeping the liquid level constant with addition solution. I cut off the bottom of one of the containers and drilled 8 holes around the perimeter and one in the middle. I suspended it from some fiberglass unistrut above the cell. I had the voltage and ammeters from various demo jobs that I had done. If I can locate the pic's I could show you my set up. I was actually quite pleased with the yeild I don't recall the exact figures it was well over 500g. And turned out some great flash powder. My aim was and is for homemade fireworks. (my sons birthday is July 4th.) I have had modest success with that
I too had several tries fail, disentagrating electrodes, power supplies failing,just to name a couple. But, persistance won through! I have since deconstructed my cell as have made enough for my purposes. I will look for my information and would be happy to share it with you if you like. There is nothing like a big BOOM especially when you made it your self.

 

[mrjeffy321]

I have to say, potassium chlorate is indeed very fun to, excuse the word, play with. I have made some pretty cool demonstrations for other people with the meager amounts I have, some of the good ones I video taped and edited on the computer which I hope to put on a website one day soon.
Most recently, I made a "rocket powered car" using a glass jar and chlorate, it didnt work as I expected from the other tests, but I did succeed in moving the car 10 inches before it burst compleately into flames.


Your set up was much more advanced than mine, certainly using more solution and prioducing much more.
But I think I will give it another go, I just need to get a power source, I might have an old trash computer with a working power supply I can for this purpose, I will look into it.
Did you make an extra effor in your cell to control the temperature and pH to get maximum efficency? When you ran it, how big of a problem was the water clouding up and dissolving electrodes?
I would be evry interested in seeing the picture you have of your setup if you can locate it.

 

[mrjeffy321]

Actually, now that I look at the power supply I have, I would have no idea how to use it in my cell. I assume it would involve destroying it in terms of it can never be used in a computer again, but I wouldn't know which wires to use or which have what current through them.

 

[Sparkee]

Power supply

Many apologies for not getting back to you sooner. If you look on your PS the connector that goes to the mother board will have a green wire with a black wire on either side. If you jumper the green with the black to the left of it you should have a fan kick on when you apply the AC to it. Then check the red and black for +5 volts if you have that you should be good to go for a Power supply. At the present time I 'am assemblying my set up so I can re-take some pic's that I cannot find. As to the temp and PH, I used a fish tank heater and was able to maintain a fairly constant 75C.for the PH in the AM I would add 10 or so cc of HCl. (Muratic Acid 30%)It seemed to work at keeping the PH within acceptable levels (7-8??) The Electrodes I purchased from a welding supply store. Around $25.00 for a box of 50. After soaking them for a couple of days in linseed oil. (To help against deteoriation of the Electrode.)Allow them to dry?? I took some Magnet wire (22 awg) and made a couple of wraps around the carbon rods finishing off with some hot glue covering the wraps.( Dont forget to scrape the wire before you wrap it.)This should get you a start. I will get the pic's in the next day or so as I get time.

 

[mrjeffy321]

If you look on your PS the connector that goes to the mother board will have a green wire with a black wire on either side.

I have looked at two, old computers' power supplys and I don't see any green wires, let alone any between any black wires.
I do have the casing and wires of another power supply (the 'guts' are gone though) and I do see the 3 wires you are speaking of there. I will tryu to get a better power supply tomarrow or at my next oportunity.

 

[mrjeffy321]

I have gotten a power supply that looks good.
I don't see any green wire between 2 blacks, but I think it will work anyway because on its sticker, it not only has the voltages and amps supplied, but also the color of the wire to get it from.

Here is what it says:
DC output: 235 W max
+3.3 V 15A (Brown), +5 Vsb 1.0 (Green)
+5 V 22A (Red) , -5 V .5A (White)
+12 V 8A (Yel) , -12 V .8A (Blue)
P.G. Signal (Orange), Ground (Black)
(+3.3 V & 5 V Total output 130 W)


If I look at the PS connector, I see these wires in this order (abbrevaited):
R = red, W = white, Blk = black, Blu = blue, Brn = brown, Y = yellow,
G = green, O = orange

Side 1,
R, R, W, Blk, Blk, Blk, Blu, Blk, Blu, Brn
Side 2,
Brn, Brn, Blk, R, Blk, R, Blk, O, G, Y

Obvioulsy my colors don't match up with yours, so I can't just 'find the green', which wires should I use? I really don't want to screw this power supply up, I was lucky to get it, I could really use your advice since you are an electrician.

another thing, let's say that I want to switch from diferent voltages/current from day to day (for various reasons), would I just use the +12 V wire and then the ground wire for example? or would I need to use the -12 V wire? but then there isn't a wire for -3.3 V.

 

[Sparkee]

I believe that you want the PG signal and it's associated wire Orng and Blk,try to jumper between them. You don't have to cut up the plug just insert the wire and turn it on. If that dosent work you could go ahead with the green and black I don't think you will damage anything as it would have to be on for that to happen(The LV side) I tried to hack an Apple Power supply,never did figure it out so I stripped it of parts. The PS I have I picked up at a used 'puter parts store for $10.00. They had about a dozen or so to chose from. I'm still gathering my set-up, I have used it or parts of it elseware on other projects. Idle hands...I'll get more out ASAP. Hope this helps.

 

[mrjeffy321]

I tested it out, and it looks like it doesn't work. I can't get any voltage through any of the wires. I tried the same thing on another power supply that I know is good and I can get 5 volts acros the correct set of wires (and 5 amps), but I can't use this power supply, I'll try to get another one tomarrow.

You said that you used electrodes, electrodes used for welding.
arent those made out of steel with some type of coating around them that is suppose to flake off? if you used those, wouldn't the water get really dirty and the electrodes would get eaten away, or am I thining of a diferent kind of electrode? this is what I was thinking about, it this the type you used,
http://www.msm.cam.ac.uk/phase-trans/2001/PICF0127.JPG

 

[Sparkee]

Electrodes...

No, the one's in that link are not the correct type. The Electrodes I used are used for carbon-arc welding, appx. 3/8 or 1/2" Dia. 16" Long, they are carbon rods that have a copper foil coating on them. I have heard them called gouging rods. I believe the length is fixed but the Dia. is variable up to 9/16". Any welding supply store would have them. Also the copper coating peels off fairly easy once it gets started. I cut them in half and soaked them in a container of linseed oil for three days. I've heard of some applying vacuum to the container, I didnt and they seemed to work fine. They will erode! I think that I replaced mine at the 1/2 way point. They were looking spindley and ragged. Well good luck on the PS. If I can help let me know. I'm working on a spark gap for a coil I built. Have a good one!

 

[mrjeffy321]

I finnally got a power supply that will work, I went through about 6 different ones before I found one that I could use. it is a different type of power supply, but I am getting a good current out of it, although it does drop drastically when in water.
So now I'll give that a try

 

[Sparkee]

Great! The I(Amps) should change once you get it into a saturated solution of NaCl,And the proper electrodes attached.I'm going to try and attach a pic of what I have gathered together.Well, I have to shrink the file size before I can upload it. Once I figure that out I'll send it along.

 

[mrjeffy321]

OK, it has begun, the electrolysis chlorate making started at about 6 amps with a fully saturated 400 mL of water (before adding salt).
this brings up a question, if I want to know the volume of my solution, do I take it after I add all the salt to it, or use the volume of the plain water I had before.

before I had 400 mL of distilled water.
after I added all that salt, I have around 450 mL of salty salty water.

 

[Sparkee]

Saturation...

I believe that in order to achieve the correct saturation the solution needs to be brought to a boil and the NaCl added until no more will disolve into it. Once that is achieved you would obtain the required amount. How did you come out as far as electrodes are concerened?? I used a Stainless Steel config. of plates and 3/8" nuts and bolts for the + and the gouging rods - arrainged circling the anode. anything in the container or in the immeadite area is subject to damage by corrosion. So prepare for that. Also are you planning to run it 24/7 ? I did and had little problem doing so. I would take the appropriate measurements every 10 to 12 hours . I also ended up attaching an hour meter that aided in the recording of the actual Amp Hours the cell operated. All said and done I ran mine for 287 Ah. I tried a few different power supplies during that and found the computer PS to be the most reliable. Good Luck! Let me know how things are going.

 

[mrjeffy321]

Well, I have logged 36 hours of running time as of right now.

Here is my stort of the first 36 hours of operation.

I started out with my good power supply (I think an 'AT' Power supply, the kind that has a switch that actually controls the AC power to it, not just some 5 volt DC signal). I was getting around 7-8 amps out of it, but the problem was that as it would run, the amps would slowly increase, by about .6 amps/hour. It didnt take long (just about 1.5 hours) for it to reach the 9 amp max that this particlar power supply would support at that voltage, and it would shut itself down. so I had to continually reset it, nut atleast I was making good progress.
I decided to let it run over night, ..., I woke up the next morning, and I don't know what exactly happened but it had turned itself off (probably overloaded), and when I went to turn it on again, I noticed that there were considerably less bubbles being mad than before, and the rather notible hum of the fan was barely audible. I switched it off, and then back on again, and now it is compleately dead, I can't get anything out of it, which is really frustrating considering what I had to go through to get it and the other uses I was using it for besides chlorate production.
I did however have one of those (PS?) power supplies that I was testing before that I could get one wire working on it, so I switched power supplies. now I am getting a remarkibly steady current of about 1.58 amps (low volts, only around 4 v), that I can and have left for the past 18 hours, relatively uniterupted.

So anyway, I broke one power supply (I hope it comes back to life, that was a really rare find for me to get that, and it was useful for othe things), and now I am using a very steady power supply, but with low current and low volts. at this rate it will take another week atleast to get done.
If only I could figure out how to get the high amps out of this working power supply, it claim to be able to go up to 25 amps, but I would be happy with 10 since that's as high as my ammeter can measure, but all I can get us 1.58.

That hour meter is a good idea, it measue what is really important, the total amps that are going into the cell during the whole trial, that was you don't have to be concerned with keeping a log of what the amps are in a log (like me) at each interval.

As for electrodes, I am using some faily dense peices of graphite blocks I had sitting around the house for a while, they seem to be working very well, under the 7 amp power supply, they made the water very dirty, but using the 1.58 amp power supply, they water is staying clean for now (I filtered it when I changed power supplies).

 

[Sparkee]

Amps

Try varying the distance between or or one block deeper than the other that is one way to adjust I,.through the resistance of the cell it self. You may also want to try a piece of stainless steel wire or ? for your Cathode. Did you look for the 5v/25A through the pin connector? the case it ground just start probing until you ID all the 5v pins then try them out. I also know that surface area of each is important. Do you know of visser's site reguarding chlorate/perchlorate production? He has done all the Math and is really quite good in his information.http://huizen.dds.nl/~wfvisser/EN/chlorate_EN.html Try that I'll see if I can find some more of those link's.My Email is jchv46m@msn.com I can send you a couple of files if you have an adress.

 

[mrjeffy321]

I have the electrodes spaced in a way that maximizes the current through the cell (they are very close together).

I will keep playing around with the power supply and try to get a better current out of it, but I don't know how successful I will be, I have went through all the wires before. All I can get are a coupld 5 v wires, but not the 5 v, 25 amp wire, but if I can get it, it will be a happy day indeed.

I am very impressed with how long I can leave this cell going, under the current conditions of around 1.58 amps, and not have to mess with it, I has pretty much been running constantly every since I started using this power supply, Slow but steady might be better than having the reset it every 2 hours.

my email address is mrjeffy321@yahoo.com if you want to send me those pictures.
And es, I have seen that page, it has been very helpful in figuring out how to produce chlorate, I have used it as a guide for both electroytic and decomposition production.
This site is good too I have found, it has a strong enphasis on electrolytic means of production:
http://www.geocities.com/CapeCanaveral/Campus/5361/chlorate/chlorate.html

 

[mrjeffy321]

That information you sent me was really, good, thanks. I will be reading over that for a while.

An update on my current cell:
I have now crossed the 110 hour marker, it has been running constantly (with only very short daily breaks to add HCl) for the past 87 hours at a fairly constant 1.58 amps. before that it was running at more amps and/or with more frequent breaks. I figure that I have about 130 or so more hours to go before the NaCl gets to about 10% concentracion, and that is when I should stop by. but I might quit early, say in around 50-60 hours, to see how it went and get my results this weekend, I am not sure what I will do yet.
Lately the efficiency has dropped since I was only able to add HCl once a day, so that adds some time to what I need to do.

I must say again how impressed I am with all that information you sent me, and how well designed your chlorate cell was.

 

[dauphin115]

Hi
Some weeks ago I started to plain my Chlorate/Perchlorate cell, the next week (I hope!) I will must to receive the material for anode and catode, I found a very little expansive system for pH control, Is a system of Hanna Industries, this system is used for pH control in acquarium, the misure system and probe cost about 175 €,if we want, we can to see this system at http://www.hannainst.com/downloads/instr/istr981411r5.pdf I found a seller in italy http://www.acquaingros.it/edisplay/cat339.htm#36
This system have exit contact for controlling device, I would to build a solution tank for HCl with a valve commanded by this exit (I think that it's not hard to build this).
I project my cell with level control of elettrolite solution and a current monitor.
The problem for me in this moment is the power supply; I have some Pc transformers, but, how we know, this transormers don't have an costant current output, I looked other website (www.geocities.com\CapeCanaveral\Campus\5361\chlorate\chlorate.html[/URL] ad example) and I try to understand the exactly goals but I need to know more about this.
I have very little experience about this topic, but I understand (I'm a chemist but my job is fireman) they are no topics/matters in italian language so if we have some advice about this I please we if you can to help me (transformer modifications or extra circuit).
All my new experience I will share with we.
Thank you very much!
Best redgards

 

[mrjeffy321]

That is a good idea about using a fish tank pH adjuster to keep your cell's pH controlled, but a little expensive for most hobbiest I would imagine (or at least for me).
As for your problem with getting a constant current out of your computer power supply, I had a similar problem when I was using an (I think it is called) AT power supply, where the power control to the computer actually turns on/off the power to the power supply. this type of power supply will give you lots of current, but I found that it also will fluxuate a lot while you leave it running. Then, due to circumstances beyond my control, I had to switch to another type of power supply, I think called an ATX power supply, where there is a contant 5 v comming out of the power supply to the computer, and the button that turns on/off the computer controls that. Using this type of power supply (far more common to find now-a-days i think), I can get a much more constant current, I think it remained constant for well over a 100 hours of continuous running for me, until the condidtions in the cell began to change drastically, but it was a relitively low current though.

I have just finished my first real attempt at using an electrolytic cell to produce chlorate, I haven't yet dried out the potassium chlorate, but so far the results look really good, and I'll decribe everything in more detail here later when it dried and I can get measurments of everything.

 

[dauphin115]

Ok, thank you for your information, about ph controller if you want I can to send you a file that I found on www about homemade pH controller, is without temperature compensation but if your cell have a control temperature you can calibrate this contorller at your temperatur's cell and all is OK, you only need to buy a pH probe (I think is impossible to homemade this probe), I'm sorry but is in Italian language, if you have problem with this language I'm very happy to help you, if you try to search on Internet about "pH controller" or controller pH" you can find some projects about this specially in amateur website of person that like aquarium hobby.
Hi Emiliano

 

[mrjeffy321]

sure, I would love to see some plans on how to build a pH controller.

I have compleated "trial 1" of my chlorate cell, dried and weighed the chlortate and tested it. Here are my results:

-mass of NaCl I started out with: 145 g
-volume of distilled water (before addeding chloride): 400 mL
-Throughout the test, I was just assuming 60% efficency, so
Total amp hours needed:460 ah
-I stopped the cell early, so I only ended up supplying 335 ah
-theorectical mass of sodium chlorate produced (at 60% efficient): 133 g
-after adding the sodium chlorate to potassium chloride to convert to potassium chlorate, max possible yeild of potassium chlorate: 153 g
-actual yeild of potassium chlorate: 109 g
-success %: 71.2 %
-actual calculated efficency would be 71.2% of 60%, : 42.7% efficient

So overall, I am pleased that I made so much in one batch, given that it took 2 weeks to make it, but I am dissapointed in the low % yeild, I though I was estimating conservativly when I said 60%, afterall I was trying to control the pH, but I ended up getting only 42.7% of what I would have gotten with 100% efficency, I wonder what the efficency would have been had I not added HCl periodically. I doubt that there is another 50 grams still in solution, I tried going back and boiling more water out to see if I could get any more, but only chloride percipitates. The over all quality of the chlorate is acceptable, it isn't as pure as I like, but that is more my fault than the cell's. I kept fairly good records of the current, volts, and calculated resistence throughout the 161 hour trial (with large gaps between record takings). There were however some reasons for its low overall efficency that I can account for, the long gaps between aditions of HCl, I wasnt home to do it and watch over it all the time, it was outside, in the cold, so it lost a lot of heat to the environment, at one point, I over diluted it by accident when adding more water to make up for the amount that was lost, early on, I didnt really have good way to gauge the pH (I still dont, I just have to asume it is neuatral when the HCl doesn't make it fizz any more), and other things that might have happened when I wasnt around.

I have started another trial, this time with tap water (500 mL) with 180 grams of NaCl, using 2 cathodes and 1 annode. I am getting about the same current, it varries slightly from 1.57 to 1.60 amps, but is fairly constant around 1.58. This cell I plan to let it go for the whole (or a very high percentage) of its total time needed to convert 90% of the chloride to chlorate, which I figure to be around 650 ah.