Synthesis of Potassium Perclorate

[Aspirin]

Please post your thoughts on this method for making KCLO4

 

I did not write this...just interested in some opinions if it would work

also any suggestions on how to improve it (if possible) are welcome

 

 

MAKING POTASSIUM PERCHLORATE

 

This proceedure is a "tried and true" method. Unlike some rec.pyro postings, which are informational, or just plain speculative, this proceedure WORKS. I have used it myself to make my own supply of perchlorate - until I decided to quit because I was making it far too fast to use.

 

This proceedure works well to make chlorates as well. The proceedure can be modified easily to make only chlorates. When using this proceedure to make perchlorate, it produces significant amounts of chlorate as a by-product. This is because carbon rods are not highly efficient in converting chlorate to perchlorate. Other anodes work better, but this proceedure was designed using easily available common materials and supplies.

 

Carbon Rods

 

Get some carbon rods from the welding shop. They are made by "arcair", and are 3/8" diameter by 12" long, and cost between 40 to 60 cents(US) each. They are copper plated, and they are used for a welding proceedure known as "gouging".

 

Cut off the top of a plastic 1 gallon milk jug. This is a good cheap source of containers for using in this proceedure.

 

Dissolve 1/2 cup of salt in 2 liters of warm water. Put this in a small plastic container. Cut out a piece of coffee can, roughly 4" by 4" with a tab extending up to connect a wire to. The dimensions are not critical. With a 6 volt battery charger, connect the minus (-) connector to the piece of coffee can. Wrap some aluminum foil on the end of the carbon rod, to improve the electrical connection, and connect the plus (+) connector of the charger to it.

 

Turn on the charger, and let it run for about 20 minutes. The copper will be removed from the rod. If some still remains, run it for a little longer till it is free of copper. Discard the salt water used to remove the copper. You can probably use a 12V charger, but the current may get too high, so you may need to reduce how much of the rod is being etched at one time.

 

Electrolyte solution

 

Make a mixture of salt and potassium chloride solutions. Dissolve roughly 2 ounces (60 grams) of salt, and 8 ounces (240 grams) of potassium chloride in 2 liters (just a bit more than 2 quarts) of hot water. There is much room for inaccuracy here, because the exact mixture is not absolutely critical. At this point, it is good to add between 2 to 10 grams of either potassium chromate or dichromate. While this is not absolutely necessary, it helps improve how much perchlorate is finally produced. The process will work without it, but not quite as well.

NOTE: Potassium chloride can be obtained as several commonly available products, such as: dietary salt substitute, ice melter (look at label for actual contents), and "muriate of potash" from farm and garden supply shops. Hagenow Laboratories carries potassium dichromate.

 

The reason a mixture of salt and KCl is used, is two fold. First, salt is more easily electrolyzed than KCl, but after it converts to chlorate (and perchlorate), it will tend form the potassium salt instead of the sodium salt. The electrolysis tends to work on the sodium salt, while the final potassium perchlorate forms, and due to it's poor solubility, tends to crystalize out of solution. Secondly, the concentration of KCl is chosen to help prevent chlorate from crystalizing out, while being too high for the perchlorate to remain in solution, which causes it to crystalize out as it is created. These concentrations may be varied, to compensate for different operating temperatures. It was designed to operate at 40C, and will work fine above that temp, but below it, you might get some chlorate crysatlizing out, in which case you might need to reduce the amount of KCl just a little. I have been using a little salt in my mixture, but someone could exclusively electrolyze KCl, without the addition of salt. The purpose of the salt is to provide a sodium salt which is more easily electrolyzed than the potassium salt. It is NOT necessary, and will probably work well with only KCl.

 

BTW, chlorates are produced here as an intermediate chemical product. Chlorates tend to be the predominant component around 1 1/2 to 2 days of operation. Chlorate could be caused to crystalize out during electrolysis if the concentration of KCl in the starting electrolyte solution is increased to nearly saturation (about 21 ounces KCl/ with 2 ounces of salt). Although I have not concentrated on chlorate production, I would expect that you could actually run it for more than 2 days - possibly up to 4 or 5 days, and keep building up a layer of largely chlorate crystals on the bottom. In that case, I would _GUESS_ that you could get around 2 pounds of chlorate after 5 days of operation.

 

Electrolysis

 

Using a coffee can for a source of steel, cut it out to form an inverted U shaped trough. Insert it in the mixture of salt and KCl dissolved in water. The (-) connector is connected to the steel. The steel U trough (similar to a rain gutter, except upside down) is setting at an angle to increase the amount of surface area in contact with the liquid. The carbon rod has some aluminum foil wrapped around the end of the rod, and the (+) connector is connected to it. The rod is positioned within the U shaped trough - under it, without touching. The charger is turned on, and he position & depth of the rod is adjusted to get 8 to 12 amps of current.

 

NOTE: A setup with the electrodes running electricity through an electrolyte is called a "Cell". This setup is commonly refered to as a cell throughout this description.

 

Let the liquid electrolyze for about 5 days continuously. Add water to make up for water lost during the process, and try to keep it roughly constant. A couple times a day, you will need to check the current level, and adjust the rod position to keep the current in the 8-12amp range. Mine has been running between 40 - 50C, but commercial proceedures keep the temp just below 40C to reduce carbon rod errosion. The rods will gradually errode away, but if you use a 6V charger, one rod will probably last for the full 5 days.You can also use higher voltage chargers, but you will probably need to connect several electrolytic cells together to keep the voltage accross ONE cell to be about 6 volts. If you use a 12 V charger, you will need 2 cells ( 12V/(6V per cell) = 2cells). If you connect more than 1 cell in series, you may need to use a voltmeter to check the actual voltage accross each cell - because it will change depending upon the resistance differences between the cells, which can be adjusted by re-positioning the rods. The purpose for the U shaped trough cathode (-) electrode, is to cause the gas bubbles formed to generate a convection flow up through the trough. This causes the chemical products produced at each electrode to mix and react efficiently. Other electrode geometries will work, some better, and others worse. The key is to cause the two electrodes to be very close to each other, and cause the chemical products to mix well to help form chlorate and perchlorates. The WORST case situation is where the electrodes are on opposite sides of the cell, causing the chlorine gas produced at the anode (+) to tend to bubble and escape out of solution into the air.

 

Crystalization

 

T he potassium perchlorate crystalizes out as it electrolyzes. When you're done, you have a mixture of black carbon, perchlorate, and some chlorate after you drain off the liquid. I generally get a layer of perchlorate crystals about 1 inch (2.5cm) thick on the bottom, which tends to be about 1 pound. Cool the liquid in a freezer to help increase the amount of perchlorate that is crystalized out, before draining the electrolyte liquid. When draining the electrolyte, save it if you want to re-electrolyze it to make even more perchlorate again. Load the crystals into a filter, and use boiling water to dissolve the perchlorate out. As it filters, the perchlorate forms nice flat rhombic shaped (almost square) flakes that float out of solution. You watch it as it cools, and watch for chlorate crystals, which tend to look like clusters of cactus needles. When they start to form (well after the perchlorate has largely crystalized out), you drain the liquid, and add some room temp water which is to be about 2 - 3 times the volume of the crystals you have in the container. Shake them, and let it stand overnight to dissolve any chlorate crystals. Then drain, wash (with ice cold water), and dry the crystals. You can purify them again by weighing the dried crystals, and adding enough water to dissolve the whole mass as if it was pure chlorate (i.e. 7g/100ml water)*. Use hot water, and then cool it down to room temp. You might even need to cool get the perchlorate to begin to crystalize (it seems to super saturate commonly). You might be able to get it started by adding a small amount of perchlorate dust as crystal seeds - if you have some to start with.. Then wash your crystals (with ICE COLD water), and dry them. That will help produce a higher purity product of perchlorate. If you want to make a chlorate-free batch of perchlorate, repeat this process again. It will be essentailly free of chlorate if you double crystalize it, and make certain you wash the crystals several times with cold water.

 

Example: 100 grams of crystals would require100grams/(7gm/100ml) = 14.3 (100 ml), or 1430 ml of water, or about 48 ounces.

 

NOTE: When harvesting the crystals, a cotton cloth makes a good filter. I wear rubber gloves, and squeeze the excess liquid from the crystals before & during washing them. Squeezing helps remove additional contaminants which are dissolved in the liquid that wouldn't otherwise be removed by simple gravity filtering. While this method loses very small crystaline particles, the loss tends to be very small in comparison to the amount of crystals harvested. Perchlorate is very easy to make, but it takes a little work. The hardest ingredient to get is patience.

[YT2095]

your source is:

 

http://www.logicsouth.com/~lcoble/stuff/kclo4.txt

 

in future, don`t just copy work, provide the Link too

 

 

 

and in answer to your question, it`s certainly A way, but it`s alot of farting around, when you can bypass many of the stages!

[boris_73]

does this method actually work then or is it a anarchist cookbook type recipe

[YT2095]

it works after a fashion, there`s easiers ways tho

[boris_73]

could you tell me the easier way then please

[Aspirin]

Never mind

[jdurg]

What I find kind of fishy is how they say that electrolyzing a solution of NaCl and KCl will produce chlorates. I have trouble believing that. The electrolysis will really just produce hydrogen gas and chlorine gas. I'm not understanding how the chlorine atoms will just decide to pick up three oxygen atoms and form the chlorate ion.

[YT2095]

they will lack the choice, it`s forced upon them to react with the electrical activation

[boris_73]

also do you have to heat the solution because it mentions keeping temperatures between 40-50c. i understand keeping the amps between 8 and 12 thats for the electrolysis but where is the heating mentioned.

[boris_73]

also where can you but potassium chloride from i have tried Holland and Barrett because i thought they would sell it but no luck also where can you buy potassium dicromate from

[boris_73]

you can buy potassium chloride in lite salt but this contains iodide will this effect the reaction anyway because im not sure how much iodide is in it

 

Edit: also how pure does the potassium chloride have to be?

[jdurg]

If you're worried about the iodide, just run a massive amount of chlorine gas through a solution of the salt. This will cause the KI to turn into KCl and I2. Then you just need to evaporate to dryness. The final step would be to spread the crystals out over a large surface area and heat it up a good deal. This will cause any remaining iodine to sublimate away leaving you with a pure KCl.

[boris_73]

i have a few more questions i all ready have what i need to make it in the house but i only have a 5volt battery charger will this do i also have a 12v one but i dont want to make two cells also how much hydrogen will come of in 5 days because i dont want an explosion while i leave it on over night also a post didnt get answerd above do you have to heat it

[YT2095]

LOL, Hydrogen is the Least of your worries

 

what are you going to do with all the Chlorine gas? would be a REAL concern!

 

and 5v is probably a little too high, what`s the current rating of it? don`t forget, it`ll be nearly a dead short!

[boris_73]

i was thinking about the chlorine but i wouldnt of thought that much would come off and it does'nt say what current is i dont think its got input: 100-240v ~ 0.4A 50-60Hz

output: 5v == 2A LPS and thats it i suppose i could leave something near it to absorb the chlorine

[YT2095]

2 amps then

 

I`de consider using a resistor in line personaly, a 100ohm at 10w should be just fine

 

as for the chlorine, don`t kid yourself, you`ll be gassed out of your bedroom within 20 mins!

[boris_73]

bugar, if there is going to be that much chlorine produced i dont think ill do it but it seems such a simple and quite easy way to make it, unless i can actually find something to absorb the chlorine but saying that there is going to be 5 days worth of chlorine produced

[Aspirin]

Just do it somewhere where it's well ventilated

[YT2095]

or leave an open bottle of Ammoinia in your room?

 

or do it next to the cat Litter Tray )

[boris_73]

why a bottle of ammonia isnt that just as bad also you can buy these cheap dehumidifers which contain some salt will that work this type just absorbs moister from the air, and realistic terms have you got a gerneral idea of how much chlorine is going to be produced as well as hydrogen because im working with a battery charger which will be striped to the wires and it might spark i also have a battery charger with the exact requirments as what YT stated, its from the phones we have had over the years my mum, dad, sister and me have a mobile phone each on contract so we get one each year that is why i have all these battery chargers

[YT2095]

the ammonia without the chlorine isn`t particularly great (but harmless in those amounts) the Chlorine without the Ammonia is Harmfull, mix the 2 and they react, forming Ammonium Chloride crystals that precipitate and fall to the ground

 

as for Humidifiers that`s up to you, you breathe Chlorine or you breathe Chloric acid? your choice

I`de go with the Ammonia soln personaly.

 

and again the Hydrogen is NOT going to be an issue! are you doing it in the Bath or a jam jar?

[boris_73]

i have a plastic buckect which can hold about a gallon of liquid its square it used to hold lawn feed i was going to do it in that with either a coke can or a paint can as one electrode and get a carbon rod, i was also going to get potassium chloride from low salt, and leave out the potassium chromate, and the charger is i have just had a look input: 200-240 V 135mA 50-60Hz output: 10 W i was going to put the equipment in my sisters room with a window open, but now i am not sure because i dont think i can get hold of ammonia unless if the cat litter will work then i will use that but again will it be able to cope with the amount of chlorine given off

[YT2095]

for a start it needs to be full of cat doo doo and pee pees for it to work

 

if you`re doing it in a 1 gallon bucket then do NOT do it indoors where there`s people around!

 

what ya need the Chromate for anyway? it`s a waste if nothing else!

 

and I`m sure your Sister`s gunna LOVE YA for that! ((

 

c`mon dude, get a little common sense here, why not try and make a small amount 1`st and see how you get on with that, and maybe after, when you know what it`s about, you can scale it up as you feel you need to or can cope with?

[boris_73]

i am going to make a small amount first i was going to half all of what the instructions said first so i make about 200-250g so that means im only going to use about 1 ltr of liquid just because i said i have a gallon bucket it doesnt mean im going to use a gallon bucket i am using that so the mixture doesnt spil over ect and my sister no longer sleeps in that room she now goes to university and her bedroom is the furthest away from mine other wise i would have done it in the spare room )) see i am using my brains i dont want to get hurt:))) also buggar on the cat poo and wee i dont think i will try that method so i guess i will just have to leave it damn!

[Aspirin]

Make a box to accomodate the container and poke some holes in the sides and make another box for the batteries and put it in the backyard. That way

the whole thing while in operation will not poison anyone with chlorine gas