KCLO3 by way of H2O + KCL

No...

It's KCL + H2O --->Electricity---> KCLO3 6H

Not 3H.

I was thinking that rikki, I know that I can get Mn02 from dry cells but I havent checked if Mn02 is an equivelant (Sp?) of Pb02. I know it wouldnt be hard to get Mn02... That and my dad got angry when I explained what I was doing. Say hydrogen gas and he calls it a bomb, make a KNO3/Sucrose smoke mix and he calls it a bomb, tell him your trying to make Ascorbic Acid/Potassium Nitrate mix and it's a non-hydroscopic rifle propellant and he calls it (You guess it!) a BOMB!

Gah, I need to ask my friend's father if I can start doing this at his place, I know he'd love helping me do this stuff.

Sorry its in Russian
But anyway here it is:
http://chembook.narod.ru/Others/KClO3.djv

I'll translate some things:
"In electrolytical production of KClO3, ClO- is oxidised at anode:
6ClO- + 3H2O + 6e- ==> 2ClO3- + 6H+ + 4Cl- + 1,5O2

Process is following: a solution of NaCl 300-310g/liter is electrolysed with iron cathode and graphite anode (without diaphragme), under 40-60*C.
Current dencity on anode 0,03-0,05A/cm2, on cathode - 0,025-0,045A/cm2. To reduce reduction of ClO- on cathode, there is added 5-6g/liter of Na2Cr2O7 and 0,5-0,6g/liter of HCl."

"Ubtained solution is then heated to 90*C, to convert the rest of hypochlorite that wasnt oxidised."

Sorry about my limited language skills

How, apart from making the solution alkaline at the start or waiting for it to turn alkaline, can one reduce the amount of Cl2 escaping?

another thread on chlorate

Duh! Good idea. Amazing how our minds can be restricted by always seeing those chemistry textbook pictures where the electrodes are positioned upright.

CCl4 does form with electrolysis of molten chlorides because of the high temperatures and inert atmosphere used.

CF4 also forms to some extent when making Al from molten kryolithe.

But I doubt it will form in aqeous solution.

BTW, CCl4 isn't that bad. It's a victim of the well known chemofear phenomenon. It has been used in lab fire extinguishers in the past and those lab assistants didn't have a particulary high cancer toll.

[Edited on 8-8-2003 by vulture]

KClO3 by Pt, Ti, KCl, H2O and electricity

Not at all, not at all, I'm still trying. I just wanted some ultra-pure (not contaminated by PbO<SUB>2</SUB> KClO<SUB>3</SUB> for use in a couple of percussion sensitive mixtures I'm very keen to try...

KClO3

Escaping chlorine

No, if you hook up the negative wire to the PbO<SUB>2</SUB> anode, you'll end upp dissolving the anode. Try the positive wire .

Leaving your probable typo aside, a battery wouldn't last 10 minutes. You need amps upon amps for days even with a small 1 liter cell such as mine.

Chlorates/Perchlorates

Sealants and Slant Angles

ClO3

Mark, that's 10 watts if your voltage and current numbers are correct. I use a battery
charger, 6 volts X 15 amps = 90 watts in my 10 litre cell. Your voltage seems a little high but
not unreasonable. As for boiling down, use glass, NOT METAL !. The hypochlorite in your
solution would decompose into chlorate and chloride at boiling but the reddish brown
color you mentioned was probably the chlorate oxidizing the iron in your bowl.

A couple of tips: During the electrolysis you should keep the brine at a constant volume
in the cell. Top off periodically with more brine as the cell level drops. Again, boil down
in glass. Find a lower voltage power source if possible.

As for testing for the presence of ClO3, read this:

Indigo Carmine is used for microscopical staining (similar to the methylene blue)
It will have to be purchased from a lab supply store. It is fairly expensive per gram but you will only need a few grams for to do alot of tests. This test in used in US Patent No. 2,392,769.
This test is extremely sensitive and will detect Chlorate levels down to parts per million.
A sample of the electrolyzed cell solution is added to a test indicator made of one gram per litre indigo carmine. The test is made by mixing 1ml of the indigo carmine with 5ml of concentrated Hydrochloric acid, and the mixture heated to boiling, To this boiling mixture, 5ml of the cell solution are added. Five parts per million of Chlorate will cause a sharp decoloration of the indicator, and one part per million can be detected.

I use this test when making perchlorates. Attached is 3 pictures of a test I did less
than 1 hour ago. I dissolved .01 grams of KClO3 in 10 ml water as the solution to
"test". In the 3 pictures from left to right.

Picture 1 shows my 250 ml reagent bottle of indigo carmine indicator. This was made by dissolving .25 grams of indigo carmine in 250 ml distilled water. It's a dark blue liquid.

Picture 2 shows a 50 ml beaker. In it contains 5 ml indigo carmine indicator and 25 ml
31% HCl(purchased at Ace Hardware). The 5-to-1 ratio of HCl to indicator is maintained.

Picture 3 shows what happened after boiling the beaker and adding 3 DROPS of the "test"
solution.

GUYS, BE CAREFUL!

KClO3 is a strong oxydizer and unstable. It's used to make matches and fireworks. In fireworks it's used to produce flash powder, and is low explosive but much powerful. The main cause of deaths in the industry of fiereworks is because of flash powder.

I almost forget.

The main route to produce chlorates and perchlorates is by eletrochemistry.

Here's my ugly-assed, for-the-hell-of-it cell (electrolyzing ice melter, probably half and half NaCl KCl). No idea what voltage (half wave rectified, doh) or current it's running at, as we seem to be out of working DMMs at the moment.

(Shoulda taken the pic an hour ago, the yellow ppt was much more interesting than the now black crud. BTW what is it? I'm not familiar with copper (from the Cu'd graphite rods) making yellow compounds.)

Tim

Graphite

So, I take it titania (TiO2) is conductive, MadHatter? I might be able to get some from the local pottery supplier and try to fuse it. I know this is a really simple question, and I probably ought to know the answer, but why are PbO2, TiO2, and Fe3O4 conductive?

I wonder if fusing the Fe3O4 with a bit of SiO2 would help it stick together? (Or TiO2 with something like Na2O)

As long as this thread's up in the air, I'll post my new cell...

Electrodes are graphite plates about 1/8 to 1/4" thick, sawn from 9" long 1 1/2" square bars (total of 55" for $30 with shipping, not bad for eBay). Very dusty black business...

Tim

TiO2

Power

And it would probably help if I actually posted the attachment

Hmm...

Nothing wrong with horizontal plates, worth a try I suppose. Vertical makes more sense from the point of gasses getting away. You also get easier access to the faces of it, rather than burning one side unevenly.

Glasses are rarely conductive, but you make a good point, Fe3O4 might be possible. Matter of fact, you need to make one (you *do* need to make one...*Jedi wave of hand*). I'd say, 80% Fe3O4 substrate, 20% clay. Might need as much as cone 10, I'll need to see if I can find an FeO-SiO2-Al2O3 phase diagram to see where it melts.

Alternately, graphite fill. Try it!

To prevent leeching, you need a dense ceramic with few pores. You can fire dangerously close to the melting point, you can use a very fine particle size (brute force method: smaller the clay, smaller the pores; pure ball clay is almost shiny after cone 10), you can add melters (borax, lime, soda) to an otherwise refractory body (clay, alumina, silica, graphite) or you can add a protective glaze. I suggest a low-melt glaze applied thinly to the surface so it mostly gets absorbed. You don't want something thick that'll interfere with the conductivity.

Tim

Well, I thought the idea was to prevent chlorine from escaping! That's why "markx" (earlier in this thread) proposed horizontal plates. Oh, and to prevent burning one side of the anode, one could only plate one side, which is just dumb, or put another (probably smaller) cathode below the anode...

Quote:

Glasses are rarely conductive, but you make a good point, Fe3O4 might be possible... (silly content removed ) ...'d say, 80% Fe3O4 substrate, 20% clay. Might need as much as cone 10, I'll need to see if I can find an FeO-SiO2-Al2O3 phase diagram to see where it melts.

I have been looking around at platinum wire for use as electrodes in a chlorate cell. The electrode will consist of the platinum wire(aprox. 50cm) coiled around a glass tube. My question, is what is the minimum diameter of wire that I should use for this? Large diameter platinum wire is quite expensive unfortunatly.

With yours hammered flat, did you ever encounter that slight erosion of the platinum would occur and corrode right through and break the electrode at that place? I figure that I will need around 50cm of platinum wire for the electrode based on a mock-up I did with copper wire. Damn platinum is expensive, anyone know any good(cheap) suppliers? I have googled my ass off searching and even made use of google adds.
Below is the electrode I hope to make, I am loosly basing my chlorate cell on the cell design from the site I took this picture from.
http://www.vk2zay.net/article.php/76



EDIT: Damn, can't get image tags working properly.

[Edited on 8-6-2005 by rogue chemist]

[Edited on 8-6-2005 by rogue chemist]

Well I made some clay substrates for anodes (not fired yet). They were made in a very nice, clean, and simple way.

Put a piece of fine cloth on the counter, then place two thin (3-4 mm thick?) parallel wood slats about 20 cm apart on top of the cloth, stick a hunk of clay (coleman raku clay was used because it's very easily fired, plenty strong, and nicely porous) in the middle of the cloth between the slats. Place another layer of cloth on top, and then use a rolling pin (y'all know what a rolling pin is, right? )
to flatten the clay perfectly. "Peel" off the top layer of cloth, then measure out how big the anode will be, and cut it out with a knife, pizza cutter, etc. Let them dry for a few hours, then take off the bottom layer of fine cloth. This method worked perfectly, and I made 4 clay pieces 4 cm x 15 cm, 2 clay pieces (for testing purposes) 3 cm x ~2 cm, and one clay piece 6 cm x 20 cm. These are nice sizes for anodes, right?

The cell I'm hoping to use will have the following specs. (everthing depends on the transformer, which may not be properly tuned, so these may not be exact)

About 4.1 L of solution will be used. (I'll make it at least 5L)

368 W ( 82A @ 4.5 V)

234 cm^2 of anode for current density of 350 mA per cm^2, which is supposedly the best. (I've got plenty of extra anode area so I can lower/raise them)

I don't know the proper current density etc of the cathode. Any ideas? I would use plain steel except for the corrosion, perhaps graphite rods would be better.

(I'm getting some diodes for the power supply. They are expensive. (Actually the radio shack diodes were cheaper than the real electronics store diodes)


Cyrus

Sorry for the double post, but I have an attachment.

Here's a simple schematic of my power supply. (see attachment)

You'll notice that there's not really any current limiting device besides a fuse. Is this reasonably safe? My concern is that the resistance of the cell could be low enough that components overheat if the electrodes are too close together, etc. But according to Wouter and other sites, there's not really any easy way to measure the current. (I could borrow a good multimeter, but they seem to think I'd need a rms meter) I'd like to have some (cheap of course) way to "dial in" the current so that when testing new configurations, I could slowly increase the current and check to make sure I wasn't giving it too many amps. I haven't bought the diodes yet, and I'm not certain how large they should be. I'm thinking 60-120 A. (I'd use a few smaller diodes in parallel instead of two huge diodes, with a resistor in front of each. )

Also, I'm not certain if I'll need to vary the voltage. I figure that if I set it at, say, 4.5 volts, it should work fine for chlorates and perchlorates, but then again, apparently MOTs have poor voltage regulation. Any ideas? I suppose a few extra taps in the transformer secondary here and there would be a good idea. Might be kind of hard when the secondary only has 4 turns.

Edit- Any ideas on what I should ground? The book I read indicated that the negative terminal was grounded in a typical full-wave rectifier.



[Edited on 9-6-2005 by Cyrus]

You must not be a dumpster diver!!!

I would not recommend using varible resistors to control the current needed for a chlorate cell. Pots with 2A+ ratings are very rare and expensive and are extremely good at converting chemical energy into heat!

IIRC light dimmers work by varing the frequency of the AC voltage to control the output power. This is also unsuitable for a DC powered cell.

I think the best way to go would to use the distance (or is it length ) between the electrodes to control current. This means you would have to have movable electrodes which can be a pain in the brain.

Another way is to use a variac, which is what axehandle used for his furnace. Good quality ones are quite expensive though and might empty the pigs belly.

So many decisions so little time...

Well, I decided to use a nice large glass jar (3.5 L capacity if I fill it to within an inch or so of the brim. That is probably too close to the top...)

That means I'll only need about 60 - 70 amps. It also means that the anodes/cathodes will not be very adjustable, because they have to fit inside of a reasonably narrow bottle neck.

According to Wouter Visser, in a chlorate cell graphite anodes run at 30 mA per square cm, while (perhaps it was that geocities place http://www.geocities.com/CapeCanaveral/Campus/5361/chlorate/... ) in a perchlorate cell they run at 200-350 mA per square cm! To those who have made (per)chlorate- what current densities on the anodes and cathodes do you use, and how well did they work? (PbO2 anodes in particular)

Also, which grades of stainless steel are suitable with PbO2? (Chromates can't form as they will ruin the efficiency.)

Edit-

~Grades of SS that are ok are type 347 and food grade is not too bad.
Other alloyes that are good are Durimet 20, Hastelloy HB-1, Hastelloy HC-3, Hastelloy C.
~

(taken from the web address mentioned earlier in this post)

Edit 2- I got a nice looking fluorescent lamp dimmer for $5. Apparently they do work by chopping up the sine wave of the 117 v input. Poor sine wave. Anyways, will this work with the power supply I am envisioning? I suppose the DC output will just be really jagged. (unless I install a large capacitor)

BTW, how the heck am I going to measure how many amps flow through this thing? Some of the multimeters I've seen only go to 250 mA. I could "borrow" a capacitor from a large motor I have, put it across the output to smooth things out, measure the voltages at the output, calibrate the light dimmer using those numbers, and then find the resistance across the cell. Which would depend on temperature, the phase of the moon, etc....

[Edited on 14-6-2005 by Cyrus]

BUMP!

I'm starting the season early for a change. My power supply is low on voltage so I'll run it for a few weeks at a time until mid-June arrives.

I happen to have this big chunk of stainless steel tubing, so I welded a plate to the bottom (welding must be like riding a bike, I only got one pinhole after the first try :cool I've still got two 1.5" square 18" bars of graphite (hmm, I do recall they're 18"...that must mean the cell is actually more like 16", not 20), so I'm just going to be lazy and drop one inside. I cut a bunch of 3/8" long chunks of PVC pipe to cover the bottom so the anode doesn't rest on a short circuit.

Tim

Real picture:



Garbage bag stuffed in the annulus to reduce fumes. Works pretty well! The spring loaded clamp holds a copper strap to the top of the bar, which doesn't corrode too badly considering. The power supply, out of view, is a microwave oven transformer I rewound for low voltage and added some diodes and capacitors to get DC.

And yes, I had just changed out the electrolyte. Gets kinda dirty as you can see. Filters cleanly through packed glass wool.

The propane torch just beside was just being used, incidentially, to cook down the hypochlorite from that run. Having a steel cell is very nice...

Last night I was also recrystallizing some KClO3 I didn't even realize I had. Turns out the last batch was significantly more yield than I had thought -- efficiency WAS good, after all. Here are some unusually large crystals.



Tim

BUMP!