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making potassium (per) chlorate


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Posted

It seems MMO is attacked when there's no current flowing through it. Maybe that's the way I destroyed my MMOs, because these motherfuckers who supply electricity switch if off sometimes in the night!

I'm putting an alarm setup. A buzzer with a small relay and a battery will do the work.

Posted

Hi all,

Again I have the same problem with the white stuff. Have an anode from Swede now and started all over but half way the first run already its pulling only 8A (After an initial of 25A)

I Know I'm half way because I have this density measuring system which tells me reasonably accurate where I am.

 

This time I did not use tap water but demineralized water.

The NaCl salt is consumer salt with 13 mg/kg E535/E536 additive (Natriumferrocyanide, Kaliumhexacyanoferraat (II))

I'm in Holland and if we will find Lead Dioxide in this salt we'll be front page!

I have about 600g of salt in my cell so not more than 8 mg of the additive.

 

post-10182-127282092118_thumb.jpg

 

Now suddenly I got this thought: Is it Silicon Dioxide?

When I look at your pictures I see no glass cells, only PVC etc. I have glass because I'm on NaCl and you don't need a big cell.

 

So question is: Could it be Silicon Dioxide? and could this stuck to the anode? and more important: How to remove it? (because rubbing is not working well)

 

Strange thing is that my platinum anodes do not have this issue. Apparently It it does not stick to platinum.

 

Damn...

 

When I looked at your picture, the picture itself didn't seem too bad. Many of mine look worse, but they still pull current. They always seem to get a bit "smutty" after use, and that discoloration shouldn't be an issue. But if the cell is no longer drawing current, THAT is definitely a problem.

 

I've had more than one report now of anodes not drawing. I have not had this problem, but there may have been a bad or contaminated batch of MMO sheet in the stock I have. I know 50AE has had the same problem. Others have not, so I don't know what is going on.

 

50AE, pdfbq, anyone who has lost conductivity, hit me with a PM and tell me exactly what size anode you want. I will cut one out of virgin deNora mesh and get them to you. If the deNora mesh fails, then I am at an utter loss. If it works, then we know that you got some bad MMO. The only other thing I can think of is failure at the weld junctions, but I think that is really unlikely. However, it can be tested by TIG welding rather than spot welding. Tig will create a puddle and an unfailing joining of the strap to mesh.

 

I haven't been coming online here as much as I've wanted to, and haven't been on Science Madness at all for a few weeks. It's been either a lousy or busy last 4 weeks or so for me, so if you've tried to contact me, I was probably in Puerto Rico, or Costa Rica, or Belize, or somewhere... and my daughter is shipping off to Afghanistan and is home on her final leave, so I'm trying to spend some time with her. I appreciate your patience and understanding with the contact stuff.

Posted

When I looked at your picture, the picture itself didn't seem too bad. Many of mine look worse, but they still pull current. They always seem to get a bit "smutty" after use, and that discoloration shouldn't be an issue. But if the cell is no longer drawing current, THAT is definitely a problem.

 

I've had more than one report now of anodes not drawing. I have not had this problem, but there may have been a bad or contaminated batch of MMO sheet in the stock I have. I know 50AE has had the same problem. Others have not, so I don't know what is going on.

 

50AE, pdfbq, anyone who has lost conductivity, hit me with a PM and tell me exactly what size anode you want. I will cut one out of virgin deNora mesh and get them to you. If the deNora mesh fails, then I am at an utter loss. If it works, then we know that you got some bad MMO. The only other thing I can think of is failure at the weld junctions, but I think that is really unlikely. However, it can be tested by TIG welding rather than spot welding. Tig will create a puddle and an unfailing joining of the strap to mesh.

 

I haven't been coming online here as much as I've wanted to, and haven't been on Science Madness at all for a few weeks. It's been either a lousy or busy last 4 weeks or so for me, so if you've tried to contact me, I was probably in Puerto Rico, or Costa Rica, or Belize, or somewhere... and my daughter is shipping off to Afghanistan and is home on her final leave, so I'm trying to spend some time with her. I appreciate your patience and understanding with the contact stuff.

 

Hi Swede,

 

Not sure if you read my post a little ways back regarding what happened with a SS pot...but it might not be feasable using a turkey fryer to chemical clean KClO4.

Posted
Hey Swede, don't feel like you owe me something. It may be my fault, that I destructed the MMO. I'm gonna make a reliable power supply system first and if then there is something wrong, I'll report it.
Posted

@50AE

I think you hold something with the problem of electricity. I notice the same thing, went we let the cell without current it have a very bad effect on electrodes. If they cut the current every night, this is a real pain to your electrodes. Something that you can do is to use a car battery. If they close the electricity, the battery will start to give current to the cell. From what I learn, you only need to get like one or two amp to your cell to mininise the electrode wear. So, with the good resistance your battery can supplier current all night.

 

@Bonny

SS from Walmart or the dollar store will always rush... Let say that it is not a really good grade of SS, no macth with the industriel grade. The best place to get some good container of SS is in an industrial scrap yard. I am use to make maple syrup with my familly and two years ago we have buy a SS pan there for boilling the syrop. We pay 100$ for a 80L thank of 4mm SS with a faucet at the bottom. I know that 150L is a lot forn a perchlorate runlaugh2.gif , but they were a lot of other stuff there that can be just correct for what you need.

 

 

Posted
I could set an emergency power supply using a 6V battery. It will switch on when there is no current coming from the power supply. I will connect a resistor in series because the cell will take so much current from the battery, that it will kill it for minutes. The resistor will let the battery pump a very small current to the cell, keeping that for hours. There will be a buzzer also. I will use relays.
  • 2 weeks later...
Posted

Hi all...

 

In the last five days, I have been attempting to replicate issues with this particular MMO material. I made up a set of tiny electrodes (Maybe 3cm by 6cm) and installed them into a 1 liter glass beaker for basic testing to destruction. The anode had a resistance of no more than 0.1 ohms across any portion of it... the MMO "skin" was conducting well.

 

http://www.5bears.com/perc/mtest01.jpg

 

http://www.5bears.com/perc/mtest02.jpg

 

I added used liquor recharged with KCl, and set up the power supply to act in a constant voltage mode, which is what most guys use, rather than constant current. I found that 5.0V drew 5.4 amps initially, and within an hour, it was up to 7.0 amps, as the chemistry stabilized. The wires were getting a bit hot, so I dialed the voltage down to 4.4V, and left it there for two days.

 

The amperage decreased as the chlorate formed. The following readings were taken over two days, all at 4.40V.

 

- 5.0 A

- 4.6 A

- 4.4 A

 

At that point, I had a healthy crop of chlorate that would be typical of a run with 1 liter. I then cut the power to the rig, and let it soak overnight, with no power, which is normally something that you would not want to do.

 

I then powered up right to 4.4V. It should have drawn 4.4A... but it did not, it drew 3.5A, indicating something had happened to the electrodes while soaking for 18 hours. Here they are:

 

http://www.5bears.com/perc/mtest03.jpg

 

http://www.5bears.com/perc/mtest04.jpg

 

I collected the product, and refilled the beaker with the exact same recharged liquor I started with. At 4.4 V, it should have drawn 5.0 amps, but it was pulling only 4.0 A.

 

The Ti cathode had a white smut on it, and some areas that looked darker when the light was just right. I used a scotch-brite (abrasive) pad aggressively on the cathode to shine it up, and cleaned up the cable contact areas. I didn't touch the MMO beyond a heavy fresh water rinse. Back in the liquor, the rig drew:

 

4.4V --> 4.8 amps

 

This was right in line with the previous run.

 

To summarize so far - soaking the electrodes un-powered oxidized the cathode or otherwise caused conductivity issues, but problems appeared to be limited to the cathode. I could see no growth or problems with the MMO. Right now, it is cooking away at 4.4V and behaving much the same as it did after the first run. I will see how this goes, and also test the conductivity across the surface of the MMO.

 

In other words, I don't have any answers about anode behavior. :glare: All I can conclude so far is that soaking will oxidize bare Ti cathode material and harm cell conductivity, but this is easily fixed with abrasives.

Posted

Swede, if you can, try two more tests:

 

-Soaking the MMO for 48 hours, then test it.

-Soaking the MMO for the same time with the connections of the switching power supply, turned off.

Posted

Swede, if you can, try two more tests:

 

-Soaking the MMO for 48 hours, then test it.

-Soaking the MMO for the same time with the connections of the switching power supply, turned off.

 

50AE if you have your electrodes In your cell for 48 hours unpowdered thats called being careless and you cant just say oh its the dodgy electricity

 

What may be a problem is the dissolved salts In the water you use

Posted

48 hour is less likely to happend. I think it is even worst if the current is swiching on and off. A better test will be to turn on and off the current every hours.

 

In my cell, I have fall to the same conclusion that Swede, the cathode always seem to be the one that get hurt. But after a lot of run and bath without current, my anode finally get touch. But it take over 8 months to die...

Posted

OK If you live in an area where the mains is not reliable, then possibly a manual or mechanical dismantle system could be viable, esp as Swede will eventually run out of electrodes.

 

Either you have a relay to dump the electrolyte off the electrodes into a holding tank on power failure, or an electrode lifting mechanism, or a pump-out system running on battery power.

 

At the simplest letting the cell run only when the power supply is reliable and taking the electrodes out and washing them with water each night before leaving the cell dismantled til morning. Yes I realise it's extra work, and you lose the overnight production time but unless you can work out a better system.......

 

OK there is the possibility of using a lead battery but the battery needed to cover the loss of mains for an hour would be huge and expensive then you would also want full UPS systems in place and possibly a 200 - 500 Amp Hour battery chosen for deep cycling application.

Posted
Has anyone tried to use bulk rock salt as the start for making sodium chlorate first?
Posted

50AE if you have your electrodes In your cell for 48 hours unpowdered thats called being careless and you cant just say oh its the dodgy electricity

 

Oh yeah, mister?

What if electricity stops 3 times per week for two hours? This is equal to 6 hours per week and to fill 48 hours, it needs two months.

 

About the alarm and emergency system...

I don't know if powering the cell at low (500mA for example) can protect the anode. What do you think?

The simplest idea is to add a tweeter which will sound, when there's no current to the cell. It will wake me up while I'm sleeping, and I'll take the electrodes off.

 

Oh, I had a nightmare today btw. I dreamt that my titanium cathode was erroded to the strip. :D

Posted
I don't know if powering the cell at low (500mA for example) can protect the anode. What do you think?

 

I don't know how much you need, but you need enough to prevent your cell to act as a batterie and to make enough mouvement to prevent some deposite on your electrode, so it will depend on your surface area.

Posted

Oh yeah, mister?

What if electricity stops 3 times per week for two hours? This is equal to 6 hours per week and to fill 48 hours, it needs two months.

 

 

There is a difference between 48hr straight, and 48hr over a series of months. It seems that the issue is that something is precipitating on the electrodes as the solution cools, reducing the effective surface area. One would think that after some time of running, the crap may redissolve as the solution rewarms. It may be interesting to repeat the experiment and boil the electrodes to see what precipitates from just lower temps, or if there is actually some sort of chemical reaction (TiO2 or something being ppct'd).

 

Either way it sounds like the best way to do this would be to just not run the cell while you sleep.

Posted

Intermittent power offers several headaches.

If the power goes off then the electrodes are poisoned,

If the standby power is little than the cell temperature will fall and things will start to precipitate.-even if the electrodes are preserved the cell may not start up well on full power.

 

What is the possibility of running the cell from early morning to late evening then washing the electrodes in pure water before sleeping and power cuts. Can you add some current in the steady state mode to make up for the lost hours? Even if not you should get a commercial life out of the electrodes this way.

Posted

Thanks guys. I installed my alarm system with the buzzer. When the current stops, the buzzer will tweet, I'll wake up and remove the electrodes.

I'll turn the cell off every time I'm not at home.

Can I use tap water to wash the electrodes?

Posted
I don't see why not, but I'd give them a final wash with distilled water or acetone or something.
Posted

Alright, the cell is kicking! The container is a 10L plastic bucket and the current is 25-27A! The temperature of the electrolyte is 45-50C. I use distilled water now, and my alarm setup works fine. I hope these live for longer..

 

And if they die...

 

I'm going to PbO2 coat the dead :) I found a very cheap Pb(NO3)2 source!

Posted (edited)

In the last five days, I have been attempting to replicate issues with this particular MMO material. I made up a set of tiny electrodes (Maybe 3cm by 6cm) and installed them into a 1 liter glass beaker for basic testing to destruction. The anode had a resistance of no more than 0.1 ohms across any portion of it... the MMO "skin" was conducting well.

Hi all and hi Swede. I was busy making fireworks but now back to my anode probs.

First to say is that I have never had any power failure as far as I know but my anode has more or less failed after about 1/2 run. At the end I was pulling about 4 Amps with an anode cathode distance of about 0.75"

I cleaned my cathode which did not help.

 

Here are some pics. Two of them before a *half* hot concentrated NaOH bath and two after (half was to see if I could see any difference).

post-10182-12755764243_thumb.jpg post-10182-12755766589_thumb.jpg post-10182-127557643271_thumb.jpg post-10182-127557739145_thumb.jpg

It helped, a little bit. I was back at 8A over 5.2V.

 

Looks like the white stuff changed into something orange-ish.

Anyway. Swede, if you can find some time, could you test your little anode in a NaCl instead of KCl solution. Maybe there is the answer. I Really don't know whats my problem.

Know the answer to it though. Buy some platinum anodes. They do not have this strange issue.

Edited by pdfbq
Posted

A little good but strange news!

After the hot NaOH bath (I dissolved about 500g of NaOH in about 750ml) Put temperature at 75C and submerged anode (and cathode) for about 30 minutes, got it out and washed it.

 

My cell runs now at 8 Amps. Not only half a day or so but already 2 full days without going down in Amps!!????.

 

I think a strong hot NaOH solution is very dangerous for the eyes and less for the skin but still harmful so take care when you try this at home :)

Posted

Sounds as though some of you need to read up on galvanic cell chemistry.

 

Once the threshold limit has been exceeded things will happen as they should, but if the power is cut to you cell then it will go about its business as nature intended.

To stop your electrodes munting when the power is out either remove them and wash them properly or have a back up battery supply that can deliver more than the threshold so that the reaction keeps happening how you want it, just a lot slower to save your batteries and electrodes.

Unless you exceed the threshold your cell will "eat" your electrodes.

 

http://en.wikipedia.org/wiki/Galvanic_cell

Posted

If you live in an area where power is not a continuous certainty, then a pumped cell may be a great help.

 

I once had a different electrolysis cell with a 100 litre reservoir and a 2 litre cell. The electrolyte was pumped by a magnetic coupled pump about 2" bore up to the cell, from which it had an overflow and a smaller bottom drain. SO, if the power went off the pump went off and the electrolyte all ran back into the reservoir. Magnetic pumps usually came (for me at least!) from film process machines, and as digital replaces film there must be piles of scrap ones! Also there were bellows replenishment pumps. These had a timer control and an eccentric setting system to get a good range of flow rates and some would take 30% sulphuric acid.

 

With a pumped cell it's essential to work within the concentration range that doesn't cause crystals to block pipes, but I found ways to use a 2" PVC pipe for the overflow and drain, and an inch pipe for the pumped feed.

  • 3 weeks later...
Posted

Well I finally bit the bullet and picked up 40lbs of crystal KCl for 19 bucks, ouch. I'm going to get planting tomorrow morning and report back here when its harvest time.

 

Also I'm considering selling the stuff at $.50 a lb as to get rid of some of it. I might make it a post in the Agora though I don't think its that important. Feel free to PM me guys.

Posted

There is a possibility that glass containers may contribute to the white smut issue, as I had an email report of a glass cell that was definitely etched post-run. It makes some sense. Here we have a material deposited on the anode that is an insulator (glass), immune to HCl (glass), immune to organic solvents like acetone or MEK (glass) - you guys get the idea. And there are different varieties of glass, some perhaps more prone to etching than others. And who knows what happens once the silicates enter solution?

 

I have been working with this material for a couple of years now. I don't know how they do it, but the material (the mixed metal oxides), while mechanically not super strong, appears to be damned inert when it comes to typical chemicals that a hobbyist would have. I've left a sample overnight in concentrated nitric acid with no apparent ill effect, for example. The only thing it cannot handle is harsh abrasion, although a soft cloth seems fine.

 

So if you are using a glass cell, and it exhibits discoloration or clouding, it might be worth it to find a different cell material. Just a thought. I've used plastics from day 1, and have never had an anode fail to conduct. The only experiment I have not tried is NaCl, but I'd be shocked if that was the problem, as plants use NaCl to produce chlorates using MMO.

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