WSM Posted June 24, 2015 Share Posted June 24, 2015 My personal opinion is that pH control done well is essential to running a cell in a glass jar, glass is certainly slowly soluble in high pH liquids, where the glass might go is debatable. I suppose I've not run the pickle jar cell long or hot enough to see the problems of alkali etching, though I did make several kilos of potassium chlorate crystals around about 2007. WSM Link to comment Share on other sites More sharing options...
WSM Posted June 24, 2015 Share Posted June 24, 2015 According to ph control, Swede said "0.057 ml of concentrated (32%) HCl per ampere, per hour, with the HCl delivery cut by 33% after the chlorate crystals begin to form." If i am going to add all the time chloride crystals, the 33% cut of HCL still must be done or not ? Swede was making potassium chlorate when he shared that suggestion. In a sodium chlorate cell, crystals don't form and drop out like they do in a potassium system because the solubilities are largely inverse in the sodium system. A one-rule suggestion doesn't work in this case. We need to measure the pH in a sodium chlorate cell often, to make the necessary corrections for optimal performance of the cell. WSM Link to comment Share on other sites More sharing options...
Arthur Posted June 24, 2015 Share Posted June 24, 2015 Patent US 3043757 says that acid ( HCl ) is added to the chloride feed stock to approximate to pH control in the cell, then fine tuning can be done less often by acid addition to the cell. Link to comment Share on other sites More sharing options...
WSM Posted June 25, 2015 Share Posted June 25, 2015 Patent US 3043757 says that acid ( HCl ) is added to the chloride feed stock to approximate to pH control in the cell, then fine tuning can be done less often by acid addition to the cell. Yes, that would work. I wonder if the amp-hour controller would work better? I still need to take the time and build one to test the theory. WSM Link to comment Share on other sites More sharing options...
WSM Posted June 25, 2015 Share Posted June 25, 2015 (edited) Patent US 3043757 says that acid ( HCl ) is added to the chloride feed stock to approximate to pH control in the cell, then fine tuning can be done less often by acid addition to the cell.Looking at this post again, I think it's a very good idea, if your system is already dialed in. Then only minor adjustments would be needed to fine tune the whole operation. Thanks, Arthur. WSM Edited June 26, 2015 by WSM Link to comment Share on other sites More sharing options...
WSM Posted June 26, 2015 Share Posted June 26, 2015 In the past couple days, I processed a 100 ml sample of the sodium perchlorate solution from the platinum cell. I used a different Buchner funnel and filter paper which improved the performance of the filtration step, despite the fact that the medium speed grade of filter paper I used, allowed some of the potassium perchlorate crystals to pass, where the slow speed grades (with their smaller pores) did not. The yield was 47.64 g/100 ml, and I attribute the difference between the LD cell and the Pt cell yields, to the lower equivalent run time of the Pt cell. Basically, I consider the two cells roughly equivalent in performance, but with hopes (expectations) of having greater electrode longevity at lower cost using the LD anode. I need to do flame tests on the samples from the two cells, and if residual sodium remains, perform additional distilled water rinsing till the samples show sodium-free results. With the right setup, I believe I can avoid the extra work and do the purification of the potassium perchlorate in a single step before drying and storing it. I'm getting closer to developing a workable system to make my own potassium perchlorate from scratch. This IS exciting!!! WSM Link to comment Share on other sites More sharing options...
Arthur Posted June 26, 2015 Share Posted June 26, 2015 For chlorate cell process control the pH is important for current efficiency and control of glass etching (IMO). HOW it's done doesn't matter, there is the AH counting method and there is the test paper test method, IF there is a steady but slightly insufficient HCl input separately or with a brine top up then actual pH tests can happen at longer intervals as the resultant pH drift will be slowed by the steady input of acid. Link to comment Share on other sites More sharing options...
THEONE Posted June 27, 2015 Share Posted June 27, 2015 By ramming bentonite clay you can form a solid mass of it. Can rhe same be done with pbo2 powder to form an electrode ? Link to comment Share on other sites More sharing options...
WSM Posted June 27, 2015 Share Posted June 27, 2015 By ramming bentonite clay you can form a solid mass of it. Can rhe same be done with pbo2 powder to form an electrode ? If only that would work. I suspect either one would lose it's integrity when placed in a liquid environment, especially an electro-chemically active, liquid environment like a running cell. So far, our best options remain plated platinum or hard (beta form) lead dioxide. As time goes on, we'll see what other options present themselves... WSM Link to comment Share on other sites More sharing options...
WSM Posted June 27, 2015 Share Posted June 27, 2015 For chlorate cell process control the pH is important for current efficiency and control of glass etching (IMO). HOW it's done doesn't matter, there is the AH counting method and there is the test paper test method, IF there is a steady but slightly insufficient HCl input separately or with a brine top up then actual pH tests can happen at longer intervals as the resultant pH drift will be slowed by the steady input of acid. Sounds reasonable, but I imagine more frequent tests with pH paper would happen till confidence in the system is gained; then I see your suggestion as viable. WSM Link to comment Share on other sites More sharing options...
WSM Posted June 27, 2015 Share Posted June 27, 2015 As I'm finishing gathering the details of my two perchlorate cell tests, and preparing to document those details in the next part of my series on Homegrown Oxidizers in the PGI Bulletin; I'm thinking more and more about setting up and running a sodium chlorate cell to provide feed stock for further runs of my experimental sodium perchlorate cells. Thanks to Arthur and others for their helpful suggestions and shared articles. WSM Link to comment Share on other sites More sharing options...
taiwanluthiers Posted June 28, 2015 Share Posted June 28, 2015 So is this stuff: http://www.ebay.com/itm/lead-dioxide-Anode-MMO-PbO2-titanium-electrode-perchlorate-chlorate-electrolysis-/161721246563?pt=LH_DefaultDomain_77&var=&hash=item25a7566363 even beta form? What about glass fusing them? You know mix them into ceramic or glass particle and fire them in a kiln? Link to comment Share on other sites More sharing options...
WSM Posted June 28, 2015 Share Posted June 28, 2015 So is this stuff: http://www.ebay.com/itm/lead-dioxide-Anode-MMO-PbO2-titanium-electrode-perchlorate-chlorate-electrolysis-/161721246563?pt=LH_DefaultDomain_77&var=&hash=item25a7566363even beta form? What about glass fusing them? You know mix them into ceramic or glass particle and fire them in a kiln? Those anodes look like the ones I have (Chinese origin). The larger one appears to be 100 mm X 100 mm and similar to the ones sold by patsroom a few years ago. Under a 200 power microscope they look like a field of diamonds. If glass or ceramic fused, I think the PbO2 would break down and it's useful characteristics would be lost (unless a very low temperature glass can be had). WSM Link to comment Share on other sites More sharing options...
taiwanluthiers Posted June 28, 2015 Share Posted June 28, 2015 That ebay site sold it at a very high price. I had one last year from a seller on ebay but I can't find him anymore. I'm wondering if anyone has one available? I guess it works well enough for use in sodium perchlorate systems? So Lead Dioxide breaks down at high temperature? Link to comment Share on other sites More sharing options...
WSM Posted June 28, 2015 Share Posted June 28, 2015 (edited) 1) That ebay site sold it at a very high price. I had one last year from a seller on ebay but I can't find him anymore. I'm wondering if anyone has one available?2) I guess it works well enough for use in sodium perchlorate systems?3) So Lead Dioxide breaks down at high temperature? 1. Yes, those are very high prices. The 100 mm X 100 mm LD anode patsroom was selling for $55 each, and the 50 mm X 150 mm ones were selling for $30 each through an eBay store. I'm sure someone could buy a group lot from China and sell them individually in the Agora or on eBay for a fair price and still make a profit. Those prices referenced from GB were ridiculously high unless they were passing on heavy import tariffs to the customers (otherwise the seller is just greedy). 2. From what I've seen so far; yes, absolutely. I suspect with good current control, they'd last a very long time and produce a large quantity of sodium perchlorate, for a reasonable cost. 3. Yes. By Google search, PbO2 melts at 290oC and definitely breaks down (liberating oxygen) at higher temperatures. My personal search for LD anodes was over several years time, and (in my experience) much preferable to making them. When I saw them at a reasonable price, I bought as many as I could afford (within reason). If I ever do make them myself, my plan is to follow Swede's example and coat LD on MMO (though the thought of plating LD on graphite sounds intriguing, also), but it makes sense to coat the cut edges of the MMO with more MMO for better adhesion of the LD, plus filled, tubular CP titanium leads would be my preference. That would be a product I could stand behind, but all the labor and effort would drive the cost up. I wish such a product were on the market, but since It isn't found, I modified one of the Chinese anodes by cutting off the titanium strap and spot welding a tubular titanium lead in place of it (to be held tightly in modified PVDF compression fittings), and filled it with solid copper wire and lead-free solder, plus tapped the top end of the leads and fitted them (the cathode assembly, too) with brass machine bolts and washers for electrical connections. They seem to work well. WSM Edited June 28, 2015 by WSM Link to comment Share on other sites More sharing options...
taiwanluthiers Posted June 28, 2015 Share Posted June 28, 2015 (edited) there's this: http://store.theamateurchemist.com/lead-dioxide-anode-2-by-6-with-4-stem/ I think it was the same place I bought the lead dioxide from last time. I think they'd work well if I could run them in a sodium system rather than potassium (the potassium system failed miserably, produced ozone and fell apart. Tried the same with platinum and the platinum completely fell apart, while producing absolutely no perchlorate) Is it possible to cast lead dioxide at all? You know press it but then sinter it at close to its melting temperature to fuse them together.... Edited June 28, 2015 by taiwanluthiers Link to comment Share on other sites More sharing options...
WSM Posted June 28, 2015 Share Posted June 28, 2015 (edited) there's this:http://store.theamateurchemist.com/lead-dioxide-anode-2-by-6-with-4-stem/I think it was the same place I bought the lead dioxide from last time. I think they'd work well if I could run them in a sodium system rather than potassium (the potassium system failed miserably, produced ozone and fell apart. Tried the same with platinum and the platinum completely fell apart, while producing absolutely no perchlorate) Is it possible to cast lead dioxide at all? You know press it but then sinter it at close to its melting temperature to fuse them together.... Ah, you've found it! That's the place I bought the LD anode I successfully used in my experimental sodium perchlorate cell. After I bought four of their LD anodes, they quit carrying them. I lost track of who they were and where I had gotten the anodes from. Thanks for posting their website. That LD anode does make sodium perchlorate (I wouldn't consider trying it for potassium perchlorate). I think the other important factor in my success with it was controlling the current input (to tight specs) by running it in constant current (CC) mode with my small DC power supply. I'm not sure, but if the LD were melted, I think you'd lose the crystal structure which may be crucial to the performance and surface area needed to operate properly in a perchlorate cell. (Edit: it might also break down to Pb3O4, which wouldn't help either). Maybe I'm wrong. Do you plan to try sintering PbO2 and trying it in a perchlorate cell? Let us know how that works... WSM Edited June 29, 2015 by WSM Link to comment Share on other sites More sharing options...
taiwanluthiers Posted June 28, 2015 Share Posted June 28, 2015 I'm not sure, I was just throwing out ideas. I kinda threw that anode away when I moved to the states because I didn't think I'd be able to make anymore perchlorates here (space and other issues) and also I don't really need to make perchlorates in the states anyways since they're so easily available. But let's hope that the EU rules don't come here (it may be difficult since that would mean Pyrodex would end up banned, and the NRA would see to it that it doesn't happen). I think this may also explain why LD anodes seem so hard to come by... realistically only people overseas would need to use it. Link to comment Share on other sites More sharing options...
WSM Posted June 28, 2015 Share Posted June 28, 2015 I'm not sure, I was just throwing out ideas. I kinda threw that anode away when I moved to the states because I didn't think I'd be able to make anymore perchlorates here (space and other issues) and also I don't really need to make perchlorates in the states anyways since they're so easily available. But let's hope that the EU rules don't come here (it may be difficult since that would mean Pyrodex would end up banned, and the NRA would see to it that it doesn't happen).I think this may also explain why LD anodes seem so hard to come by... realistically only people overseas would need to use it. Seriously?!! Just because you can buy something today, doesn't mean it'll always be available to buy. I don't make chlorates and perchlorates because I need to, I do it because I want to. I want to know how to do it, before I need to do it. It's a truly liberating feeling knowing I can make things for myself, and being self-sufficient. Political winds may blow this way or that way, but If I'm able to supply my own needs,...then Who Cares?!! WSM Link to comment Share on other sites More sharing options...
taiwanluthiers Posted June 29, 2015 Share Posted June 29, 2015 Politically anything can happen, and even the act of making perchlorate itself would be illegal. Heck even being of a certain color/race/religion could be illegal one day too. I'm not trying to suggest anything, and honestly I'd really love to try making perchlorate proper, however I'm not even sure I could get the lead dioxide anode from that seller again, seems he stopped stocking it so realistically it looks like the platinized anode he has is the only thing that's going to work. Link to comment Share on other sites More sharing options...
WSM Posted June 29, 2015 Share Posted June 29, 2015 (edited) Politically anything can happen, and even the act of making perchlorate itself would be illegal. Heck even being of a certain color/race/religion could be illegal one day too.I'm not trying to suggest anything, and honestly I'd really love to try making perchlorate proper, however I'm not even sure I could get the lead dioxide anode from that seller again, seems he stopped stocking it so realistically it looks like the platinized anode he has is the only thing that's going to work. For perchlorate production, I ran both an LD and a platinized anode, and frankly they both worked. The trick of my success was the DC power supply with constant current capability. If you can find such a supply, you'll be able to tightly control the power to the cell and maximize it's performance. As for LD anodes, don't give up. Sooner or later some will appear at a decent price. Till then you could use a platinum anode for perchlorates. WSM Edited June 29, 2015 by WSM Link to comment Share on other sites More sharing options...
taiwanluthiers Posted June 29, 2015 Share Posted June 29, 2015 Where do I even begin to look for such a supply? my last problem was I used a computer power supply. How much do supplies like this cost? Link to comment Share on other sites More sharing options...
WSM Posted June 29, 2015 Share Posted June 29, 2015 (edited) Where do I even begin to look for such a supply? my last problem was I used a computer power supply. How much do supplies like this cost? Try eBay item number 271588660952 0-16 Vdc, 0-20 A, power supply with constant current capability. Price is about $115 US, delivered. WSM Edit: If you buy one of these power supplies, replace the leads with heavier gage cables (larger diameter wires) to carry the current or your output will be severely limited. Edited June 29, 2015 by WSM Link to comment Share on other sites More sharing options...
Arthur Posted June 29, 2015 Share Posted June 29, 2015 Don't knock the ATX psu! as a source of inspiration a free second user one will provide a steady voltage, with some care you could hack the voltage control to become 5v variable Link to comment Share on other sites More sharing options...
WSM Posted June 29, 2015 Share Posted June 29, 2015 (edited) Don't knock the ATX psu! as a source of inspiration a free second user one will provide a steady voltage, with some care you could hack the voltage control to become 5v variable If you get them for free, why not?! I have a friend who gets all the used computer power supplies he wants for free because he networks with a computer repair guy. I've never used one, but I've studied the process of adapting the computer PS to provide power for a chlorate cell. For experiments and exploring the unknowns, I love the adaptability of the higher-end DC power supplies which offer 0-10 Vdc and 0-(enter a number) Amps, which also have CV and CC capability; so I can adjust and monitor the various aspects of the individual cell, till I dial it in. Once I know the parameters and limitations of a particular cell setup, I can tailor a (less expensive) fixed power supply to run it. At this point in my studies and research, I'd only use the computer PS for a chlorate system with MMO and titanium electrodes, where there's little to go wrong and the parameters are fairly well understood. With the perchlorate systems (and my hard-to-come-by anodes), I prefer to limit the current to them to minimize the impact on the anodes till I understand the system better and can proceed with confidence that I won't destroy my setup. The beauty of using computer power supplies is their universal availability; they're everywhere. WSM Edited June 29, 2015 by WSM Link to comment Share on other sites More sharing options...
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