hashashan Posted January 29, 2008 Share Posted January 29, 2008 I believe that you anode will have a trip to the dead anodes land if youll start making perch with it. Anyway, the only problem in raising the viltage is the temperature. heat=IV(very roughly) ... I=10 .. and the lower V will be the less heating you generate. You better bring the electrodes closer instead of raising the voltage.However if there is no other way.. please use 12V .. I always do...... but be ready to cool the cell in some way.btw. what is the size of your cell? Link to comment Share on other sites More sharing options...
WarezWally Posted January 29, 2008 Share Posted January 29, 2008 Cannot get the electrodes any closer Running a 7L cell so heat shouldn't be a major issue Link to comment Share on other sites More sharing options...
hashashan Posted January 29, 2008 Share Posted January 29, 2008 Yeah 7L is ok for 10amps at 12V, Anyway a good way to drive the heat off is to pump water through a plastic pipe inside the electrolyte. What is the cathode? if it is some steel then I would recommend you to use a steel pipe wound around the anode and to pump the water through it. Link to comment Share on other sites More sharing options...
WarezWally Posted January 30, 2008 Share Posted January 30, 2008 CP titanium mesh, was given to me pretty much for free (paid shipping) by the guy who I got the anode off. http://myworld.ebay.com/bobbr48 Damn good of him Link to comment Share on other sites More sharing options...
WarezWally Posted February 4, 2008 Share Posted February 4, 2008 Started my 7L KCl > KClO3 cell, decided to add some potassium hydroxide at the start (I have a serve dislike for chlorine). The whole thing has turned yellow and smells of chlorine (it is my understanding that when hydroxide is added it gets trapped and forms potassium hypochlorite, does pH really matter?) There is about a inch of KClO3 crystals on the bottom already, I plan to dissolve and re crystallize them once to remove hypochlorite and excess chloride. Anyone see any problems? Link to comment Share on other sites More sharing options...
tentacles Posted February 4, 2008 Share Posted February 4, 2008 Keep in mind that K hypochlorite won't decompose on boiling like Na will - at least, not in my experience. Also, at 12v your Ti underneath the MMO will passivate aggressively when/if it becomes exposed to electrolyte. Higher Ph is fine but efficiency suffers. Are you using an additive at all to help efficiency? Any idea what MMO it is? I haven't tested my MnO2 anodes yet, but they reportedly last several months making Chlorate, and are very cheap to make/remake. I am going to try a different method of putting SnO2 on my to-be-PbO2'd anodes in the next few days. Link to comment Share on other sites More sharing options...
WarezWally Posted February 4, 2008 Share Posted February 4, 2008 Cannot run it at 12v (well not a KCl solution) as it draws stupid amounts of current compared to NaCl (like 30A) so its sitting happily on 5v atm. No additives but efficiency is not really a major issue for me. Link to comment Share on other sites More sharing options...
brok3n Posted February 15, 2008 Share Posted February 15, 2008 Just sent a quote request off to a company in india for graphite and Ti substrate PbO2 anodes. Link to comment Share on other sites More sharing options...
WarezWally Posted February 16, 2008 Share Posted February 16, 2008 Processed my cell today, It had been running for about a week and a bit and there were a good inch or two or crystals on the bottom. I let it sit in the sun for a while to see if it would remove some of the chlorine smell to no avail so I simply drained all the liquid and spooned out the crystals. Got a rough yield of 500gm from that but I needed to remove the hypochlorite and excess chloride. I dumped the 500gm into 900ml of water and started to boil it, nearly all of the crystals dissolved. It was then left to cool and was then placed in the freezer (I love having a spare fridge) so I could precipitate as much product out as I could. A few hours later I had a beaker filled with lovely large square crystals with minimal chlorine smell. The MMO anode has been great, absolutely no wear at all and the cell is very clear (a bit yellow though) Link to comment Share on other sites More sharing options...
tentacles Posted February 16, 2008 Share Posted February 16, 2008 Nice! Do you have an estimate of yield? I wonder what metal oxide that anode is, is it one of the yellowish tinted ones? Those could be TiH showing through a doped tin oxide. I wish I knew of a good way to destroy hypochlorite in these potassium solutions. If you boil that liquor down you'll get nice yellow cubic crystals of K hypochlorite. I plan on taking my MnO2 anodes skinny dipping later this week, we'll see how that goes. I really need to pick up that Ti from Frank's place to make some good cathodes, and more anode stock. Link to comment Share on other sites More sharing options...
InRainbows Posted February 17, 2008 Share Posted February 17, 2008 I'm trying at making my first cell, I'm using sodium chloride in water 40 grams to 100ml,9 volts. When I put in both the wires , one of them starts bubbling then eventually turns the solution a yellowish gold color. I didn't put in a pipe to vent away gases, is this supposed to happen? Is it just chlorine turning into solution? Link to comment Share on other sites More sharing options...
tentacles Posted February 17, 2008 Share Posted February 17, 2008 What type of anode and cathode are you using? You can't just stick wires in a chloride salt cell and expect anything but a bad smell unless you use the right materials. If you don't vent the gases properly, everything in the general vicinity of your cell will be slowly covered with a white powdery crud. Also, it's very dangerous not to vent, not only are the gases poisonous, they can be explosive! Link to comment Share on other sites More sharing options...
InRainbows Posted February 17, 2008 Share Posted February 17, 2008 that's probably why. I just stuck lengths of copper wire with + and - current. I let it run its course, and it didn't form any gases. it just turned all of the water orange, and with a bunch of orange crystals in it. Anyone know what it is, by any chance? Link to comment Share on other sites More sharing options...
Mumbles Posted February 18, 2008 Share Posted February 18, 2008 Cuprous Oxide would be my best guess. (Cu2O). It's actually red, but in fine form, it may appear orange. Link to comment Share on other sites More sharing options...
jacob Posted February 18, 2008 Share Posted February 18, 2008 That is awesome Wally, looks like what came out of my cell only more, are you runing Potassium or Sodium chloride? tentacles, thanks for the tip, I was wondering why my cell was covered in that junk, I just drilled a hole in the top and let the chlorine flow. (outside ofcorse). Link to comment Share on other sites More sharing options...
InRainbows Posted February 18, 2008 Share Posted February 18, 2008 would I have any use for it or can I dump it? Link to comment Share on other sites More sharing options...
Mumbles Posted February 18, 2008 Share Posted February 18, 2008 It's a blue colorant, but likely so contaminated with sodium it is more or less useless. Link to comment Share on other sites More sharing options...
tentacles Posted February 18, 2008 Share Posted February 18, 2008 Wally: Looks good, I've got a bag full of those nice square chlorate flakes around here somewhere from my graphite run. I keep telling myself (and others) that I'm really going to put those MnO2 anodes to work soon, just haven't gotten around to it still. Link to comment Share on other sites More sharing options...
WarezWally Posted February 18, 2008 Share Posted February 18, 2008 I'm running a MMO anode in KCl at about 6A @ 5v in a large 7L cell (ill post a photo) Anode is great, I reckon it will make cubic shitloads of chlorate before wear sets in. Got it from this guy http://stores.ebay.com/JJFLASH-PYRO-LAB-COMPUTER-SUPPLY Currently drying the chlorate in open air, yield is pretty much spot on 1lb. Apparently this anode *may* be able to do perchlorate, I'll email the manufacturer and see what they say. It may drastically reduce its life but even if it lasts a year that would be great (rated for 20 doing chlorate) Link to comment Share on other sites More sharing options...
WarezWally Posted February 18, 2008 Share Posted February 18, 2008 http://www.vk2zay.net/article.php/146 lol, looks like he cooked a expensive platinum anode making perchlorate. Ill see what he thinks about making perc with MMO Link to comment Share on other sites More sharing options...
InRainbows Posted February 19, 2008 Share Posted February 19, 2008 My cell is still in the idea phase, and I was wondering what temperature lead reacts with potassium nitrate to form lead dioxide, I've heard it makes quite a good electrode. Link to comment Share on other sites More sharing options...
Arthur Posted February 19, 2008 Share Posted February 19, 2008 The big problem with perc production occurs as you approach completion. as the chloride concentration falls too low the electrodes erode. There was one "amateur" perc cell in the UK running well a while ago at a cell current round 80 amps. Production by electrolysis at single figures of amps tends to make so little product that it isn't worth the bother, or the electrode cost. Link to comment Share on other sites More sharing options...
Mumbles Posted February 19, 2008 Share Posted February 19, 2008 My cell is still in the idea phase, and I was wondering what temperature lead reacts with potassium nitrate to form lead dioxide, I've heard it makes quite a good electrode. Part one of that question, it doesn't. KNO3 doesn't have a strong enough oxidizing potential to get it to PbO2. It will yield PbO, which is not nearly as useful. Part two. You can't simply prepare PbO2, and press/glue it into an electrode. It must be plated on to get good electrical conductivity. See the rest of this thread for more info. Link to comment Share on other sites More sharing options...
InRainbows Posted February 19, 2008 Share Posted February 19, 2008 Lead(IV)Oxide (lead dioxide) A dark brown or black solid with a rutile lattice, PbO2, which is insoluble in water and slightly soluble in concentrated sulphuric and nitric acids; r.d. 9.375; decomposes at 290 C. Lead(IV)Oxide may be prepared by the oxidation of Lead(II) Oxide by heating with alkaline chlorates or nitrates. Excerpt for the Oxford dictionary of Chemistry that I got the idea from. If you heated lead with KNO3 you'd probably get PbO, reheat to get PbO2. About that second problem, I dunno. Link to comment Share on other sites More sharing options...
hashashan Posted February 20, 2008 Share Posted February 20, 2008 reheat PbO and youll get Pb3O4 .. maybe some PbO2 will be still present .. but you do need it pretty pure. just react lead nitrate with hot NaOCl Link to comment Share on other sites More sharing options...
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