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making potassium (per) chlorate


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Posted

No, it was just yesterday and must have been transient. Today they snapped right in.

 

As long as you don't have any bandwidth problems linking them from your site, I wouldn't worry about it. I just suggested it because we have literally NO bandwidth restrictions.

 

M

Posted

I appreciate the offer. I have no real bandwidth issues, and my disk space is about 5% full. A lot of my pictures I link to a number of different sites, and it gives me total control over the process. I go from camera, to Picasa, to EasyThumbnails (which takes a 120K image down to 40K with little loss in integrity), to WS_FTP in about 2 minutes. It's just a matter of use and comfort for me. :)

 

I still appreciate your help with the index.html problem. My brother, who is no slouch with HTML, was amazed that it could be done at all. Now, my basic web site (.com) defaults to a "scientific" web page, while .com/index.htm goes to my original hobby site.

Posted (edited)

I started my first test run of KClO4 today!! :D . Finally moved onto the second step. I'm doing a test with a ~3l batch containing 210g of KClO3. The cell is now running at 3A and about 6.5V, using the 6V setting on a car battery charger. I am using a Pt anode and 2 Ti cathodes spaced 1/2" apart. The electrodes will likely be moved closer together in future to increase the current. I will watch though, as the cell temp might still rise and current will increase.

 

The ozone really stinks, and the cell will have to be vented on the next run.

 

Edit:

 

I shut the cell off after about 1 hr of running. The ozone smell is too much in the house to run without a good vent tube going outside. The temp had risen and it was running 3.5A.

The cell liqour is still clear, but now has a dark (purple) tint :unsure: . Not sure WTF that's all about. I'm going to get a vent going and start it up again right away.

Edited by Bonny
Posted
The ozone really stinks, and the cell will have to be vented on the next run.

 

Edit:

 

I shut the cell off after about 1 hr of running. The ozone smell is too much in the house to run without a good vent tube going outside. The temp had risen and it was running 3.5A.

The cell liqour is still clear, but now has a dark (purple) tint :unsure: . Not sure WTF that's all about. I'm going to get a vent going and start it up again right away.

 

Congrats on getting it going, but the "purple" has me thrown. Are we talking grape juice purple, or much lighter?

 

Remember the viciousness of these electrolytes. O3 is one of the more reactive molecules we know of, and you may be having a severe oxidation of an incompatible cell material from ozone or something else, thus tinting the liquor. While it's down, look for erosion or chemical decomposition of all of your components, and replace if something really stands out.

 

If the purple color isn't that bad, I suspect it'll clean up with ease when you recrystallize, but it is definitely an odd and curious effect.

Posted
My test cell is up and running now with a vent :D . I still catch a whiff of ozone now and then but much better. Currently running 3A @ 6.5V. It should be done on Sat. If it works, I'll be closing the gap between electrodes to increase the current and scaling up to a 18l cell.
Posted

Sounds good, Bonny. PM sent.

 

I have worked a bit more with the tubular Ti shank concept, and one of the real problems is the poor conductivity of the Ti tube. We tossed about some ideas like filling the tube with lead or an alloy of lead, and using that to carry the bulk of the current. I bought some alloys and also some 1/4" tin wire from Rotometals and attempted to fill a 1/2" OD Ti tube (flattened on one end for welding to an electrode) with tin so that the tin will carry the bulk of the current rather than the Ti, a poor conductor.

 

It was painfully easy, AFTER heating the Ti to dull red:

 

http://www.5bears.com/perc/tubes07.jpg

 

The interior was scored for mechanical purchase:

 

http://www.5bears.com/perc/tubes08.jpg

 

And it was filled with pure tin using a simple propane torch:

 

http://www.5bears.com/perc/tubes10.jpg

 

http://www.5bears.com/perc/tubes12.jpg

 

The end of the tube was cleaned up, drilled and tapped 1/4" X 20, and is ready to accept a crimp terminal:

 

http://www.5bears.com/perc/tubes14.jpg

 

The whole idea was to create an electrode shank for production - solid and leak-proof mounting using a PVDF compression fitting, and an ability to carry a current that puts the Ti tube skin to shame. An earlier attempt using a brass cap to make the connection:

 

http://www.5bears.com/perc/rst04.jpg

 

So far, so good. Tin drills and taps well. I think this will work. :)

Posted

After 2 runs, I've pretty much ruined my jewellery trade Pt anode. :angry: I have a bag with ~120g of recrystallized perc and maybe 300-400g drying now. I don't know if it is indeed perc, still waiting on some chems for testing and purifying.

The crystals are almost sugar like- much smaller than the chlorate.They are a real bitch to get dissolved to filter and re-xtalize, keeping my hopes up that I do have perc.

 

Anyway, once my new anode arrives I'll be setting up another cell and will get some pics up then.

Posted
Purple screams manganese. Given MMO/platinum anodes it's not clear how it's getting in but maybe you have some stainless steel or Ti alloy dissolving somewhere.
Posted
Purple screams manganese. Given MMO/platinum anodes it's not clear how it's getting in but maybe you have some stainless steel or Ti alloy dissolving somewhere.

 

Maybe the Ti substrate on the anode or the cathode itself. There is no SS in there. The (whatever it is) is insoluble though and is easily filtered out.

Anyway I ended up with around 470g of dried x-tals which I hope is perc or mostly perc. I still have to test for chloride before proceeding on cleanup, but I think that will be very low or nil after several washings, recrystallization and another couple washings.

Posted
The first thing that came to mind was Manganese too. Is is possible MnO2 is part of the mixed metal oxide coating by any chance? The other HIGHLY unlikely thing that came to mind was Titanium (III) Chloride.
Posted
The first thing that came to mind was Manganese too. Is is possible MnO2 is part of the mixed metal oxide coating by any chance? The other HIGHLY unlikely thing that came to mind was Titanium (III) Chloride.

 

I was using a Pt coated Ti anode and a Ti cathode, unless somehow there was some remnant from the MMO used making the chlorate. The chlorate feedstock I used was washed, dossolved/filtered/recrystallized and washed again, so I would think it was quite clean.

I think Tentacles mentioned titanium chloride when I was talking to him about the ppte.

Posted

Wow, I did not know about Titanium(III) Chloride so I looked it up. It is preperable by electrolysis assuming you have Titanium(IV) Chloride in very acid solution. Plausable, and the solutions colour would be discharged by air, which could explain how you could have a clear purple solution one moment and a filtered clean one the next. Did you get an actual purple ppt Bonny? The solid purple hexahydrate is oxidised slowly by air but ought to be more soluable than that. We are assuming chloride, it could be the chlorate or perchlorate potentially.

 

It seems weird that such a reduced species might be produced in a cell of such a high oxidising potential as to vent ozone, but then only half the cell is oxidising. I also threw away the idea of Vanadium(II), quite a low oxidation state but Ti/V alloy is common in structural Ti products.

 

Would Ti(III) be stable enough to be visible in a solution of chlorates and perchlorates? My information runs out.

Posted

I've only seen Titanium (III) in solution once, and it was quite a pale purple, though I don't think it was the chloride. The Ti(H2O)6 3+ ion is pretty pale, but maybe the chloride would be more strongly colored. I hear it is quite strongly colored as a solid.

 

I found this, and the high concentration of chloride or HCl in solution would make sense with a more visible color.

 

http://www.woelen.nl/chem/Ti+F/Ti+F.htm

Posted

Here is my new chlorate setup, it's been running since 8 days and I got a 300 grams batch of KClO3. Thanks a lot to Swede for the electrodes :D.

 

Cell info:

-Cell body material - unknown. It doesn't seem to be polyethylene, it's quite strong. I've put in in a second bucked in case it leaks one day.

-Electrodes - MMO anode and straight titanium cathode from Swede.

-Current - 7.5 amps at 5 volts, it was 9.5 in the beginning. Maybe the low temperatures have to do with this.

-pH - I'm keeping it at about 6.5-6.7 by adding a little quantity of HCl every day.

-Power supply - Chinese low cost 400W ATX switching PSU

Cell.rar

Posted
Wow, I did not know about Titanium(III) Chloride so I looked it up. It is preperable by electrolysis assuming you have Titanium(IV) Chloride in very acid solution. Plausable, and the solutions colour would be discharged by air, which could explain how you could have a clear purple solution one moment and a filtered clean one the next. Did you get an actual purple ppt Bonny?

 

The ppte was purplish, not anything like in the pic Mumbles found. More of a VERY slight tinge in the cell liquor. Once filtered, the paper had the ppte on it and appeared purple/maybe brown. This seemed much worse when I first started the cell. On the second run there was almost no discoloration. My Pt anode is toiast now so I'll see what happens when I get my new one and get a cell running again.

Posted
I wouldn't expect anything as intense at that solution. It was purposely done. A little bit of TiCl3 wouldn't be too surprising actually. It seems a lot less reactive than I was first lead to believe. It could have been as simple as a bit of impurity on the surface of one of the electrodes that reacted off on a first run.
  • 4 weeks later...
Posted (edited)

After a week or running the cell from pH 6,4 to 6,8 by adding HCl from time to time, I achieved efficiency of 85% !!

I got two kilos of KClO3.

Now I've changed the cables and the cell is working much better. The amps are 17A now. It seemed I had a great current loss from the old connections.

 

What I'm doing now, I'm saving money for equipment to make barium chlorate!

Edited by 50AE
Posted

My new perc cell is now up and running (second Pt anode :angry: ). I have the electrodes spaced 1/4" apart and the cell is drawing 9.5-10A. The new problem I have is that my voltage had dropped to 5.2V. Last time (before I killed my anode) I was getting 6.5V @ 3-5A. Maybe the battery charger loses voltage when the current goes up?

I started it up yesterday afternoon. I checked it this morning and there were no x-stals in the bucket.I improved the connections and am now getting 5.5V.

Anyway, I'm going to run it for a few days to see what happens. Will perc form at this lower voltage?

 

I also have an air pump/bubbler running in the cell to circulate the liquor.

Posted

Will perc form at this lower voltage?

Yes, it will.

I have started my first Pt cell yesterday with 5.2V (because I don't have 6 or 7V) and this morning my methylene blue drop turned instant purple when I tested.

I think every voltage will create perchlorate but 6 or 7V should be the most efficient.

Posted

Yes, it will.

I have started my first Pt cell yesterday with 5.2V (because I don't have 6 or 7V) and this morning my methylene blue drop turned instant purple when I tested.

I think every voltage will create perchlorate but 6 or 7V should be the most efficient.

 

My 5.5V seems fine.I harvested the cell today. The perc is dirty-contaminated from (most likely) unclean parts as well as maybe the black hose I used for the bubbler. But anyway, although I haven't tested with methylene blue (don't have any) I'm sure I have several hundred grams of perc.I'll filter and recrystalize in the next few days...and get a new batch going of course.

Posted

Good job Bonny!

 

My chlorate cell is not turned on now, the weather became horrible again. It got warm today and the snow melted. I hope it will keep that way, and I will launch the cell again.

My latest batch of KClO3 was harvested two weeks ago and it weighted 1.5kg! I did the math and it seems my chlorate costs me 2$ per kg with all expenses - KCl and electricity, with the recrystallization included.

It costs me less than KNO3 does :D

Posted
Good job 50AE! 1.5 kilos is an excellent harvest. Have you had any issues with the welds on this set? You are definitely one of the more aggressive users, and are kind of a "guinea pig" for the others. ;) If these welds fail (and I don't think they will - they are very deep and strong) then I'll have to start TIG welding them, which I don't want to do.
Posted (edited)

Good job Bonny!

 

My chlorate cell is not turned on now, the weather became horrible again. It got warm today and the snow melted. I hope it will keep that way, and I will launch the cell again.

My latest batch of KClO3 was harvested two weeks ago and it weighted 1.5kg! I did the math and it seems my chlorate costs me 2$ per kg with all expenses - KCl and electricity, with the recrystallization included.

It costs me less than KNO3 does :D

 

You must have quite a bit stocked up by now.

I've never calculated what it cost me to make chlorate...but as I can't get it any other way it is worth it for sure.

 

Good job 50AE! 1.5 kilos is an excellent harvest. Have you had any issues with the welds on this set? You are definitely one of the more aggressive users, and are kind of a "guinea pig" for the others. ;) If these welds fail (and I don't think they will - they are very deep and strong) then I'll have to start TIG welding them, which I don't want to do.

 

I know I had nothing but great results with your electrode sets. I ran 20-25A and produced ~20kg of chlorate and the anode looks good as new.

 

EDIT: My dried "dirty perc" weight is 680g. My cell efficiency is horrible, around 40% based on a formula from Swede posted here: http://oxidizing.110mb.com/chlorate/runtime.html

Still better than (another) cooked Pt anode.

Anyway, still happy though, as chlorate feed stock is plentiful and easy to make. The next step is cleaning some up for use...and making more of course.

Edited by Bonny
Posted
EDIT: My dried "dirty perc" weight is 680g. My cell efficiency is horrible, around 40% based on a formula from Swede posted here: http://oxidizing.110...te/runtime.html

Still better than (another) cooked Pt anode.

 

That page is from Dann2's excellent web site. We all got sick of trying to calculate efficiencies, and reduced the math down to what is on that page. But remember, the number you get is pessimistic. At the moment you kill power to a potassium-based cell, you have 2 separate quantities of potassium-oxidizer... the crystallized stuff, and that which remains dissolved in the liquor. The latter can be quite high, and is normally no big deal, because we recycle... nothing lost. But if you want a really accurate efficiency answer, you have to add, to the dry weight, the amount of chlorate or perc that remains dissolved. So you take the volume of the cell, the temperature, and determine how much oxidizer would dissolve at that temp and volume; add that to the dry yield for a much closer REAL efficiency.

 

The understanding of efficiency with perchlorate cells, from a hobby perspective, is WAY behind that of chlorate. A good MMO setup with pH control can crack 90%, but I honestly have no idea what would be considered "good" for a Pt-based perc cell. It is a matter of gathering data. Maybe 40 to 60% is the best we can expect. I'm not sure.

Posted

That page is from Dann2's excellent web site. We all got sick of trying to calculate efficiencies, and reduced the math down to what is on that page. But remember, the number you get is pessimistic. At the moment you kill power to a potassium-based cell, you have 2 separate quantities of potassium-oxidizer... the crystallized stuff, and that which remains dissolved in the liquor. The latter can be quite high, and is normally no big deal, because we recycle... nothing lost. But if you want a really accurate efficiency answer, you have to add, to the dry weight, the amount of chlorate or perc that remains dissolved. So you take the volume of the cell, the temperature, and determine how much oxidizer would dissolve at that temp and volume; add that to the dry yield for a much closer REAL efficiency.

 

The understanding of efficiency with perchlorate cells, from a hobby perspective, is WAY behind that of chlorate. A good MMO setup with pH control can crack 90%, but I honestly have no idea what would be considered "good" for a Pt-based perc cell. It is a matter of gathering data. Maybe 40 to 60% is the best we can expect. I'm not sure.

 

 

I'm not really worried about efficiency at all, just figured I'd see roughly where it was at. The main thing is that I'm making something I can't easily get..if at all these days. Also, I think I lost a noticable amount washing the product. I used a 200mesh screen as a filter to avoid waiting forever for it to run through filter paper (coffee filters).

IMO I think I'm definatly having some success.

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