What Went Wrong in My Attempt to Make Potassium Chlorate?

[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.

 

[dauphin115]

Very well!
I know that is very difficult to control current efficency I read more and more on www about this, they are some experimental setup for chlorate cell, I read about electrode position into cell, anode on the bottom and catode on the top (anode under catode) the Cl2 gas that are formed at the anode to go up and "meet" the OH- that are formed at the catode, this setup help the formation of chlorate (not more but..), stirring the solution is another way to increase the current efficency because help the dissolution of Cl2 gas.
pH controller:
about this, the probe measure the concentration of H+ ions, the output of probe is a measure in mV that the pHmeter convert in pH value, I don't know more about this but I know that the presence in solution of ionic/cationic species don't influence the mV value ( it depend only on H+ concentration) so is possible to measure the value of mV (with sensible mV meter) and build an apparat that add in the cell HCl if the value of mV change.
The current efficency is more influenced by the value of the pH and you can obtain a good current efficency value only if you control pH.
I have a question for you; You use chlorate for your experiments or use it for preparation of perchlorate?
Hi Emiliano

 

[mrjeffy321]

For right now atleast, I use the chlorate I make for experiments (pyrotechnic, rockets, ...).

 

[Sparkee]

PH Meters...

Glad to hear that it produced for you! Please let me know how your devices turn out. In my case I was able to achieve some spectacular results. One problem was getting the Al processed to a fine enough mesh. If it is not you end up with a fountain instead of a "BANG". BE CAREFUL!
Check out this link for PH/MV/T meters, WWW. Grainger.com

 

[mrjeffy321]

In the mean time, while we wait for my current chlorate cell to compleate, here a question about contruction of the cell.

I know you, Sparkee, made a pretty eleborate cell with lots of electrodes and a cover and it looked very well made.
My cell isn't quite so big, I am reluctant to make an eleborate cell just yet before I can pretty much perfect my process I will use and before I gather the materials needed (and get a better power source).
Right now, what I have is a plastic penut butter jar, about 5 inches tall and 3 inches wide. As my electrodes I use 3 (2 cathodes, 1 on either side of the annode), made of recangular chuncks of graphite. This basic system seems to work well, but my main problem, which I didnt get into before on my last trial (probably because it was outside), is that the copper wire I use to connect the power supply to the electrode gets corroded very easily and breaks off, this breaking the circuit. I have a lot to prevent this, I have wrapped it in tape, then I covered it in hot glue, then I covered it in some rubber cement type glue, then I covered it with both glues, then I got some water putty that dried hard around it and used that, and in all cased, with in 24 hours (many times less) of continuous running, the wire corrodes and needs to be replaced. the problem is occurring because of the chlorine gas being made at the annode that is rising up and corroding the copper, it seems to get through any barrier I give it, eventually.

Any suggestions on how I can prevent this from happening, or at least delay it much longer?

 

[pack_rat2]

...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...

I've been away for a little while due to the holiday season, but now I'M B-A-A-ACK...! ;) As for purification, the accepted method is recrystalization. Heat up water to the boiling point and dissolve as much KClO3 as it can take, and a little more. Pour off the clear solution and cool it down. Pure crystals of KClO3 will precipitate out. Just keep doing that until all the KClO3 has been processed.

 

[mrjeffy321]

Hey, it has been a long time.
But wouldn't this method inevitibly leed to the loss of lots(7g/100mL) of perfectly good KClO3?
For example, if I decided to purify 100 grams, I would need to use about 1.4 Liters of water to dissolve all of it and I would get very little back.
Or is the idea insted not to redissolve it, but rather just get it wet and thus dissolve the impurities?


Any suggestions on the electrode problem?

 

[Sparkee]

Having the cover on my set up helped ,also I used magnet wire (26 ga.) you might try shrink tube also. On the end of the electrode where the wire attaches I used hot glue and shrink tube for some protection and tried routing the wires up and away from any obvious problems. At about the halfway point of the process I did replace all the electrodes as they were eroded to the size of pencil lead. I didnt have any of the wires corrode. I think that having the tight fitting cover helped by allowing me to route the chlorine gas away from any problem areas. Make no mistake corrosion will be an issue! I had mine set up in my shop even with an exhaust fan I still had problems. Anything that was not stainless steel was affected. Several of my hand tools in the vicinity have a nice layer of rust. I still find chloride/chlorate accumulated in places when the humidity is high. From that I learned that when next I run a cell it will be outside.

 

[mrjeffy321]

I find I get best results using a combination of hot glue on the bottom and this runnery type glue called, "goop" on top. Right now I added a middle layer of wax to see if that will do any good, but the jury is still out on that.
I think I will try to set up some type of lid to divert the gasses away, but this will be hard considering how low to the water leve the wire is. it might be a better idea if I just redesign the whole cell, but I wanted to wait before I did that until I got at least one reliable, high amperage, power supply I can count on now breaking, otherwise I'll have to wait years to get a bucket of NaCl(aq) turned into NaClO3.

 

[Chronos]

You can buy the stuff at the grocery store. It's called lite salt.

 

[mrjeffy321]

The 'lite Salt' you are referring to is actually a mix of Sodium Chloride and Potassium Chloride, thus containing less (lite-er on the salt) "salt" than normal salt. But I would need pure Potassium Chloride, no sodium chloride (that is just a by product of this reaction), so I use something called, 'NoSalt', also at the grocery store, but a tad more expensive.

by the way, the wax idea worked terribly.

 

[pack_rat2]

Hey, it has been a long time.
But wouldn't this method inevitibly leed to the loss of lots(7g/100mL) of perfectly good KClO3?...Or is the idea insted not to redissolve it, but rather just get it wet and thus dissolve the impurities? Any suggestions on the electrode problem?

You just say the solution you have at the end of the purification, until your're ready for the next batch. Sure, you'll always have some left over, but if you keep making it, that amount doesn't increase. And you MUST dissolve it in order to purify it, since the impurities are locked into the crystal structure. As for electrodes...platinum is what's recommended! I bet you just loved to hear that. I've read something about stainless steel and carbon rods, for those of us who aren't rich.

 

[pack_rat2]

I posted a link on the thermal method; it also has info on electrolysis. Here it is, again:
http://www.wfvisser.dds.nl/EN/chlorate_EN.html#thermal

 

[mrjeffy321]

platinum is what's recommended!

I, no problem, I will just reach into my vault and pull out a couple bars.
I am unsure on how well platinum would work, or for that matter silver or gold (what about nicrome wire?) would work almost as good, but would a platinum electrode work perfectly with no corrosion or erroding? or would it eventually. I was under the impression that no matter what I used, it would get corroded but at diferent speeds.

Saving the water used for purification, good idea. But then it gets complicated if you want to do a batch a diferent size than the amount of water you have, .. time to get out the measuring cup and esimate what is dissolved already.

Does anyone know what the average purity of KClO3 is without purification, through either method (if there is a diference)?
Then once it is purifies, doesn't it get to be pretty close to 100%


Sparkee [or whoever wants to answer], a while back (many posts), you said that you used an "hour meter" to help you measure the total amhours into your cell. I was looking around, considering getting one, but I don't really know what to look for, I found a wide range of styles, prices and desciptions. I foun something called an hour meter, but it is used to meaure the time elaped on electrical motors and what not and I am unsure if it is the same thing you had. also, there seems to be specifcations on the voltage that the hour meter uses, does this matter if my cell is not within the hour meters range?
example of what I found:
http://amos.shop.com/amos/cc/main/ccn_search/st/%22hour%20meter%22/sy/productsx/ccsyn/260/prd/8197242/ccsid/324920718-20893/adtg/02100541

 

[Sparkee]

It was (is) just a standard analog hour meter using line voltage. Run in series with your power supply line side. The one I use came off an old compressor control panel that I demo'ed a while back. I set it up so that when I switched on the power supply it would engauge a relay and begin recording. Through this I also ran the heater ( aquarium type) so that when I performed the daily maintainance(Ph,etc..) that the heater would also shut down. If you happen to forget to un plug the heater when you pull it out bad thing's can happen. The glass tube encasing it will shatter exposing the element and you have 120v exposed. Not good! I admit that my setup was probably over done. Had a lot of time on my hands. But, What the heck keeps me out of trouble.Let me know if I can be of help. The one your link showed is DC I suppose it would work. Mine ran off 120v so I was able to keep it farther away from the cell (corrosion,etc...)

 

[pack_rat2]

"...[Y]ou said that you used an 'hour meter' to help you measure the total amhours into your cell..."

If you can't find one or can't afford one, you can do it the old-fashioned way. Put an ammeter in series with the circuit, and make a note of the current. Then, at periodic intervals, check the current and record it. For each interval, calculate the average (sum of the current at the beginning and end of the period, divided by 2), then multiply that value by the length of the time interval. Then add up the values of all the intervals for the total. This method isn't as accurate as using a meter that measures current*time continuously, but it should be more than adequate.

 

[mrjeffy321]

that is essentially the way I do it now, but it is so time consuming, keeping all those records of what the current was at each interval.
also, when I can't tend to it all the time (like when I goto sleep), a lot of times it stops because of some problem, and i never know when to estimate the stopping time was. if I can find one cheap enough, it think it would worth it to me convience wise to get one.

I am roughly into my 440th amp hour on my second trial of my chlorate cell, only about 210 more to go.

 

[mrjeffy321]

OK, it is finsished after long last, my second trial is done, the Chlorate has been extracted, dried, and weighed.

Stats:
-Started with 180 grams of NaCl
-dissolved in 500 mL of water
-should have taken 650 ah to convert 90% of it at
-estimated 55% efficency (what I estimated it would be from the begining)
-I ran it for the full 650 ah, by my log (which inclues soem rounding, but more on that later).

Theoretical maximum amound of KClO3 that could have been made by convering 90% of the 180 grams of NaCl: 272 g.

Actual yeild: 140 grams
% success: 51.5$
Actual efficency: 28.3 %


This is pathetic, I am ashamed of these results, it is stuff like this that makes me think I forgot a decimal somewhere because this is horrible!
I let this cell run for the entire month of Feburary to get the 650 ah needed, then I spend a week extracting it and letting it dry, crush it up and weight it, and all I get is a measly 140 grams, (just a small jump from my last cell), and I should have theoritcally gotten 272 grams.
sure is a lot compared to how much I used to be making, but I spent so much time on this, changing electrodes, keeping careful logs, adding HCl, ... and something must have gone terribly wrong for me to get only 28.3% efficency, I could have done nothing and got better than that. I did do some rounding and estimating, but I don't think this could have made that huge an impact on my results.

This really makes me want to redesign my cell, but there are so many complications, I don't know where to start.
if/wheh I redesign it, its main purpose would be to produce chlorate, but I also want to be able to collect/divert all the gasses (speratly) that come off the electrodes.

 

[redwraith94]

mrjeffy321: Boiling bleach decomposes it from 3 x NaClO to 1 x NaClO3, 2 x NaCl

Platinum electrodes can be used, but they have to be uber pure, even .01% rhodium/some other similar group metal will give the electrode a set service life...this is considering electrodes that are usually copper core, niobium alloy 1st plating, then platinum over-plating (usu ~100-250 microns thick or so)

Graphite works fine, and they are much cheaper, I just got a quote for platinum clade copper rods. 2 x rods 1 foot long each with a 100 micron plate 1/4 inch full diameter...90 dollars US...too much money for an electrodes w/ ~5,000 hrs service life? lol.

Finally, don't be ashamed of your results. A big thing that comes into play for electro-chemistry is current density, temp, ph etc. You really want fairly large electrodes for your setup. I am doing research right now, because I am also looking to make a Chlorate/sugar/Ammonium sulfamate/dye based smoke bomb for the fourth.

 

[Letda]

hey guys, I am new at all this so don't judge me right away. I'v been researching how to make the potassium chlorate for about a week now w/o actually doing a lab. I'v read everything that had been posted, but I am still a little lost. I was just wondering if one of you could break down the steps in lame'ns for me. I run an IQ of 147, knew frued before i knew freud, but chem... i sometimes wonder. If anyone can talk one on one with me to help me understand i might be of some value to your conquest. Just E'mail me at -letda13@hotmail.com-. otherwise ill be reading up on your findings and starting my experiments my self. Ill post everything i find i promise :)

 

[mrjeffy321]

Hello, I have been researching/making potassium chlorate for about 9 months now, so I have gotten plenty of experience by now.

Do you have any specific questions, or do you just want general information on the process(es).
Like redwraith94 mentioned, this is a popular time to start making KClO3, only about 2 weeks left until the 4th of July (and all the homemade fireworks that go with it [taking all necesary precautions of course]).
If you want to make a lot of Potassium Chlorate in a short amount of time, I would go with the decomposition of hypochlorite method (boiling bleach), but if you have more time and are patient enough, the potential for gain using the electrolytic method is much greater. I myself prefer the electrolytic method, but I have been plagued by bad luck with it also, using hypochlorite is certainly provides much quicker results (and some might consider it easier).
I actually have a batch of KClO3 drying right now.