285 replies to this topic

[alany]

MMO electrodes generally won't work well for Perchlorates. They will work for making Bleach or Chlorate though. The PSU for a chlorinator would be an idea source for a chlorate cell if you can get one cheap on eBay.

[pkhow]

I was refering to DSA anodes described as for chlorates
http://www.eltechsys...orate_Cells.asp

[pkhow]

There are DSA anodes designed for a range of Industrial uses. What intended use for an anode best suites Perchlorates.
http://www.eltechsys...s.asp#Trivalent

[alany]

DSA or Dimensionally Stable Anode is just a marketing term for various technologies based on MMO (mixed metal oxides) on various substrates, typically Ru/Ir/Ti oxides on Ti. They will work for Chlorates quite well, especially if designed for commercial Chlorate production. I'd love to get a large one for a Chlorate cell, using graphite is wearing pretty thin, its a bugger to filter out.

Perchlorate production should really use Pt on Nb because of the higher voltages typically used and the oxygen overpotential required for reasonable efficiency. Pt on Ti will work for amateur use as long as you don't run it with too high a voltage. I can break-down the Ti oxide layer in my cells by ramping up the voltage, this will rapidly destroy the Titanium rather than just passivating it. Niobium on the other hand will just passivate, even up to 30 volts or more. It forms a beautiful purple-blue anodised layer:

http://nexus.cable.n...90/p0004764.jpg

OT: by controlling the voltage applied and the duration of the anodising you can make quite pretty looking coatings on Niobium, ranging from subtle yellows through blue purples to dark browns. This is used commercially on body jewelery for a dyeless anodising process that can produce quite striking effects that are very robust and completely biocompatible.

Also note that "aerospace" Ti alloys will generally not passivate at all, and are rapidly destroyed in anodic conditions. On the other hand, they are cheap and excellent cathodes. Their conductivity is fairly poor but much better than graphite and on par with mild steel or stainless, and they are far less likely to contaminate the cell even under cathodic conditions as mild steel and some stainless alloys will.

Substrate and rising posts for anodes should be as pure Ti as you can get. Mechanical connections in the electrolyte between passivating metals like (Ti, Nb, etc) intended to carry current will eventually fail as they passivate, it is best to spot-weld the anode together if you have the equipment. Ti hardware carefully cleaned and then tightened up until it galls will last for a while but it isn't cheap.

Commercial anodes are great in this respect, all that hard work is already done for you. Trust me when I say Niobium to graphite connections are near impossible to maintain for more than a few minutes, even using Silver in between.

[littlejohny]

I have found a computer PSU that looks promising it can deliver 30amps at +5volts only thing is, I have no bloody idea how to work out wich 2 wires I need to use, here is the link for the PSU can someone please help me work out how to do this, Thanks

[alany]

The ATX colour code goes like this:

Black: GND
Orange: +3.3V
Red: +5V
White: -5V
Yellow: +12V
Blue: -12V

The current capabilities of each rail are generally printed on the label.

The Green wire is the /enable and needs to be tied to ground to cause the PSU to put out any voltage on the main lines. The Purple wire is a seperate low current +5V rail and is the standby line,it always supplies as long as the PSU is plugged in, even when the Green line is not grounded. The Grey wire is a signal line to the motherboard, it is high (+5V) when the PSU is delivering regulated power.

The same colour codes apply to the aux, floppy, ATA, and ATX power connectors. All the wires of the same colour are tied together back inside the PSU. If you are confident with mains-power work you can open the PSU and modify it to include a power switch (if it doesn't already have one), binding posts for the rails you are interested it, meters, LEDs etc. You may also wish to modifiy its regulation feedback to bring the 5 V rail up to 6 or 7 volts (as long as all the components can survive the modification). This will be quite valuable if you wish to use the PSU to supply chlorate cells. Needless to say, you have to know what you are doing to attempt to modify the supply.

You will need to load the 5V rail for the PSU to regulate properly. Most ATX supplies only regulate the 5V or 3.3 V rail, the rest are based on the regulated one via transformer ratios.

[pkhow]

There seems that there are a few routes to get to KClO4. Is the simplest and safest ( least chlorate contamination) route to construct a chlorate cell and start with NaCl? Then use cell using an anode for perchlorate as you discussed earlier to get to NaClO4. Then as in available litrature make your KCLO4 by double decomposition of KCL and your NaCLO4.
The other route seems to be starting with KCl ---- to KCLO3 --- to KCLO4 but seems this is a lot more difficult.

[pkhow]

Possible Ideal Power supply for electrolitic conversion.
Is there any interest in Power supplies available in a short form kit of parts.
Output wiring and a box is all that you need to find. Supplied would be a Power cord, fuse and fuse holder, 500VA transformer for simplicity and reliablity, rectifiers, 30 or 60amp meter, control PCB ( capable of controlling ( 0 ~ 12volts) with a wiring Loom for the controll
An example at 6volts you could draw up to 80 amps where at 10 volts the limmit would be 50amps.
A laymans type assembly diagram is available and the only skill you need is to be able to do very basic soldering. Very simple kit to wire! They are under $100 and well under with a small Transformer at 40 amps. A small moderfication would make them capable of higher voltages but with correponding lower amperage.If there would be any interest i will see if they can add it to there webb Site.

[alany]

The details have already been discussed in the (Per)chlorate cell thread, but to make Perchlorates you should make it via Sodium Perchlorate because of its high solubility. Potassium Chloride has insufficient solubility to be practical in a Perchlorate cell.

However I can tell you from experence if you run a Perchlorate capable anode in a Potassium Chlorate cell significant amounts of Perchlorate will be made once the Chloride level gets low. This is a bad situation for the anode life and if you want pure Chlorate, but it happens despite Chlorate crystalising out.

If you want pure and no-fuss Potassium Chlorate use graphite in saturated Potassium Chloride. For Barium Chlorate use Sodium Chloride and Graphite then precipitate out with Barium Chloride. For Potassium Perchlorate use Sodium Chlorate with Platinum or Lead Dioxide, make the Sodium Chlorate from Sodium Chloride and graphite.

You can go from Sodium Chloride to Sodium Perchlorate in the one cell, but it will reduce the life of your anode. With homebrew Lead Dioxide electrodes this isn't as much of an issue as with expensive Platinum ones.

[littlejohny]

The ATX colour code goes like this:

Black: GND
Orange: +3.3V
Red: +5V
White: -5V
Yellow: +12V
Blue: -12V

The current capabilities of each rail are generally printed on the label.

The Green wire is the /enable and needs to be tied to ground to cause the PSU to put out any voltage on the main lines. The Purple wire is a seperate low current +5V rail and is the standby line,it always supplies as long as the PSU is plugged in, even when the Green line is not grounded. The Grey wire is a signal line to the motherboard, it is high (+5V) when the PSU is delivering regulated power.

The same colour codes apply to the aux, floppy, ATA, and ATX power connectors. All the wires of the same colour are tied together back inside the PSU. If you are confident with mains-power work you can open the PSU and modify it to include a power switch (if it doesn't already have one), binding posts for the rails you are interested it, meters, LEDs etc. You may also wish to modifiy its regulation feedback to bring the 5 V rail up to 6 or 7 volts (as long as all the components can survive the modification). This will be quite valuable if you wish to use the PSU to supply chlorate cells. Needless to say, you have to know what you are doing to attempt to modify the supply.

You will need to load the 5V rail for the PSU to regulate properly. Most ATX supplies only regulate the 5V or 3.3 V rail, the rest are based on the regulated one via transformer ratios.

Confusing!

From looking at this it looks like there is about 150-200 wires coming out of the PSU,and I have to find 2 so basically I need to use a black and a red wire .

This chlorate cell is turning out to be a lot more complicated than I originally thought.

[maximusg]

Don't get confused mate its not that complicated. Most of the leads, are just copies of the same thing, some with different plugs is all. Inside a computer there are different standards for different componants, ie, a couple of plugs for the CD-ROMs, a couple for fans, floppy drive, and Motherboard power. but they are all in that list alany posted. Use any of the red and black, as you need.

[littlejohny]

So basically I can use any red and black wires to power my cell.

[pkhow]

Use any red or black but join a few reds and blacks together if you intend to use more than 5 amps so they share the amperage

[littlejohny]

Use any red or black but join a few reds and blacks together if you intend to use more than 5 amps so they share the amperage

Ah, I was thinking last night there is no way 2 of those little skinny wires could withstand the resistance of 30 amps.

If you are confident with mains-power work you can open the PSU and modify it to include a power switch (if it doesn't already have one), binding posts for the rails you are interested it, meters, LEDs etc.

I was looking at DC Amper and volt meters yesterday, $24 for a DC meter 0-20amps, $24 for 0-20volts.

[alany]

Dick smith prices hey?

Panel meters are fine, but they are expensive.

Personally I'd recommend you buy two cheap multimeters from Jaycar if you want concurrent measurement of voltage across the cell and current though it. Unfortunately most multimeters only have a 10 A DC range, but Jaycar sells current measuring shunts which are absolutely perfect for high-current (per)chlorate cells. (Check out QP5412 QP5414 and QP5416) Just put a multimeter across one on voltage, they are also much more robust than the shunts inside multimeters. The whole setup will cost less than $30, two DMM and the shunt.