WSM Posted December 7, 2014 Posted December 7, 2014 Two cells allows us to use Pt only where it is essential which is cheaper True. Use MMO for the chlorate phase and platinum for the perchlorate phase. WSM
WSM Posted December 7, 2014 Posted December 7, 2014 (edited) The issue with Pt electrodes is simply cost. It's available by post you just have to pay for it. The issue with Lead Dioxide is toxicity, you will have disposal issues with the plating solution and the electrodes, and may have lead in the final product. If anyone is familiar with electroplating chemistry then perhaps we could find a good method of producing a run of lead dioxide electrodes and dealing with the waste. I imagine there may be trace amounts of lead in the final product. We won't know till we dial in the proper cell parameters and make some perchlorate. Then we can test for lead in the final product. We can test for lead in the Chinese perchlorate, if they do, indeed use LD for their process. I do have a sensitive and specific test for lead, but it's qualitative and not quantitative. A sensitive quantitative test is really called for, here. To quote Pooh, "Oh bother...". WSM Edited December 7, 2014 by WSM
Arthur Posted December 7, 2014 Posted December 7, 2014 The problem with lead is that the first failure of the electrode and you have a slurry of lead paste to clean up, with a Pt electrode you expect to lose about 12g per ton of perc which would be a lifetime's use for most of us.
WSM Posted December 7, 2014 Posted December 7, 2014 (edited) The problem with lead is that the first failure of the electrode and you have a slurry of lead paste to clean up, with a Pt electrode you expect to lose about 12g per ton of perc which would be a lifetime's use for most of us.Then again, since we're discussing a sodium perchlorate cell (everything useful in solution), a simple filtering operation should remove the lead debris. One key factor in cells with platinum anodes is to keep the chloride level as low as possible. High chloride levels are a major contributor to platinum anode failure (or at least degradation). WSM Edited December 8, 2014 by WSM
schroedinger Posted December 7, 2014 Posted December 7, 2014 Also if you get so much lead debris on the bottom of the cell it would be no problem to drain the cell and flush out the lead. Filter of this and give the lead to your next hazardous waste disposal. Since the lead is comming of the anode it will be nearly 100% pbo2 a d this as god as insoluble. And for the stuff in solution don't bother too much a out it, you don't touch the liquer with bare hands or? Also you wear a respirator while working with thd chlorate/perc.Specially after recrystallizing the ammount of lead should be near to zero. If you aren't sure you can add some drops of sulfuric acid to the solution of Na per to precipate the lead as lead sulfate
MrB Posted December 8, 2014 Posted December 8, 2014 Also if you get so much lead debris on the bottom of the cell it would be no problem to drain the cell and flush out the lead. Filter of this and give the lead to your next hazardous waste disposal.What? No! You of course save it, for a rainy day. When you ruined enough anodes, you get a nonreactive bag (Fiberglass cloth?) and put all the filtered waste in it, stick whats left of an anode (or a good one) in it, and use that as an anode.I saw that somewhere, was it swede that went that route? Cant remember. Anyway, save the stuff.B!
Arthur Posted December 8, 2014 Posted December 8, 2014 Swede's Blogs tell his progress with PbO2 electrodes, but anyone pouring lead salts down the drain may get noticed as the sewage plant stops, it's very unfriendly to the environment.
MrB Posted December 8, 2014 Posted December 8, 2014 If your pouring it down the drain, your doing it wrong. But that said, buying the anode is the only option for me, i want to make perchlorate, not start a (second) chemistry lab. For someone that wants to make their own anodes Sweden probably is one of the worst, and best places to do it. The acids needed cant be freely bought at useful strength, but when your done, disposing of it is as simple as labeling it, and sneaking it out on to one of the pallets in one of the hazardous turn in spots. And when i say sneaking, i mean, grab 2 cases of spent motor oil, and a case of this stuff, and carry it all out in plain sight. Nobody will ask any questions, and when they go to recover the stuff, everything is tested, thoroughly, and if there is markings on the container to help decide what it is, they are happy. Acids generally get recycled. Not sure how they would deal with this stuff tho.B!
WSM Posted December 8, 2014 Posted December 8, 2014 Specially after recrystallizing the ammount of lead should be near to zero. If you aren't sure you can add some drops of sulfuric acid to the solution of Na per to precipate the lead as lead sulfate Some interesting thoughts. If things go according to plan (and they don't always), there'll be no recrystallizing. The potassium perchlorate will drop out of solution almost instantly since it's roughly 1% the solubility of sodium perchlorate. Afterward, a simple wash with cold distilled water will remove any residual dissolved salts. It occurs to me, instead of dropping sulfuric acid, why not titrate with sodium sulfate solution, and any lead will still drop out as the sulfate (without the added hazard of handling acid)? WSM
WSM Posted December 8, 2014 Posted December 8, 2014 What? No! You of course save it, for a rainy day. When you ruined enough anodes, you get a nonreactive bag (Fiberglass cloth?) and put all the filtered waste in it, stick whats left of an anode (or a good one) in it, and use that as an anode.I saw that somewhere, was it swede that went that route? Cant remember. Anyway, save the stuff.B! I believe those sorts of ideas appear in sciencemadness. The technochemistry section would be a good place to search. Lead dioxide is used for different types of pyrotechnics (industrial or military, if memory serves), so save it regardless. WSM
WSM Posted December 8, 2014 Posted December 8, 2014 (edited) Swede's Blogs tell his progress with PbO2 electrodes, but anyone pouring lead salts down the drain may get noticed as the sewage plant stops, it's very unfriendly to the environment. No, you will be noticed, and hunted. Government agencies take a very dim view of polluting, especially with toxic materials. If you create toxic byproducts, be responsible and contain them. Usually, when handling soluble or mixed-with-water types of chemicals, concentrating by removing as much water as possible, is the first step. Mumbles and others with strong chemistry backgrounds, can offer sound handling suggestions. WSM Edited December 8, 2014 by WSM
WSM Posted December 8, 2014 Posted December 8, 2014 Speaking of handling toxic byproducts, years ago I treated a fair amount of magnesium powder with potassium dichromate. After vacuum filtering the coated magnesium, I had a large flask of bright yellow potassium chromate to deal with. Wanting to avoid a waste issue, I mixed it with a soluble copper salt and created a mass of brown copper chromate which I filtered out and dried. The plan is to put the copper chromate in a covered crucible and roast it into copper chromites, the highly sought after catalyst for APCP propellants. WSM
Arthur Posted December 8, 2014 Posted December 8, 2014 The original site by Dan2 said that the bagged electrodes were poor and disfunctional, which is why Swede (in his blog) said about electroplating a carbon rod with stronger crystal forms of lead dioxide, saying how the plating conditions were critical to getting the most suitable form of lead dioxide.
WSM Posted December 8, 2014 Posted December 8, 2014 The original site by Dan2 said that the bagged electrodes were poor and disfunctional, which is why Swede (in his blog) said about electroplating a carbon rod with stronger crystal forms of lead dioxide, saying how the plating conditions were critical to getting the most suitable form of lead dioxide. If I'm correct, Swede plated LD onto DeNora MMO on CP titanium mesh. If he had plated graphite, he'd be in a position to try the sodium chloride to sodium perchlorate method mentioned previously. Swede was concerned about sodium contamination and always avoided using any sodium source in his chlorate and perchlorate efforts, so even if it were LD on graphite, he'd probably not have tried the chloride directly to perchlorate method. WSM
schroedinger Posted December 8, 2014 Posted December 8, 2014 Yes he used mmo. But an other question, some of you really think about putting old anodes into a bag to form a new one?How much perc do you need? I would assume that you will need at least 5 broken anodes to form one new one in a bag. Using the cheaper china anodes this is the point after making at least 100 kg of perc and all test i read about bag anodes described a fast failure of the anode?
WSM Posted December 8, 2014 Posted December 8, 2014 (edited) Yes he used mmo.But an other question, (1)some of you really think about putting old anodes into a bag to form a new one?(2)How much perc do you need?I would assume that you will need at least 5 broken anodes to form one new one in a bag. Using the cheaper china anodes this is the point after making at least 100 kg of perc and all test i read about bag anodes described a fast failure of the anode? 1) No, never considered it.2) None. I have sufficient perchlorate for my needs. My research is just that, research. I like knowing first hand how it's done and that I could, if need be, produce my own chlorates and perchlorates. WSM Edited December 9, 2014 by WSM
MrB Posted December 8, 2014 Posted December 8, 2014 How much perc do you need?Considering that i don't intend to stop making pyro for another 60 years or so... A lot.B!
schroedinger Posted December 8, 2014 Posted December 8, 2014 Considering that i don't intend to stop making pyro for another 60 years or so... A lot.B!Ok well that makes it at least half a ton, it's really time to consider moving to the us or so (well still at least 5 years to go for that)
WSM Posted December 9, 2014 Posted December 9, 2014 (edited) Ok well that makes it at least half a ton, it's really time to consider moving to the us or so (well still at least 5 years to go for that) Hopefully, whenever you get to the US the scene hasn't gotten to where it's as bad for hobby pyrotechnics as everywhere else in the world. Things are still accessible now, and I hope that doesn't change. If it does, these discussions on making our own oxidizers will be all the more neccessary. WSM Edited December 9, 2014 by WSM
Arthur Posted December 9, 2014 Posted December 9, 2014 To make chlorate it matters little what chloride you use, but to make perc it may be much easier on the electrodes to have sodium chloride going to chlorate going to perc as the solubilities are better making the solutions easier to electrolyse without electrode damage.
WSM Posted December 9, 2014 Posted December 9, 2014 To make chlorate it matters little what chloride you use, but to make perc it may be much easier on the electrodes to have sodium chloride going to chlorate going to perc as the solubilities are better making the solutions easier to electrolyse without electrode damage. Yes, I'm inclined to think so, also. It's been my suspicion, for a while now, that making sodium perchlorate is much easier on the anodes than the potassium salt would be (for the reason you mention). There may be other reasons too, that aren't obvious to us yet. We'll see... WSM
MrB Posted December 9, 2014 Posted December 9, 2014 Ok well that makes it at least half a ton, it's really time to consider moving to the us or so (well still at least 5 years to go for that)So, by the time my current supply is gone, i'll be ready to move to the US, and with any luck they wont consider me a terrorist anymore, so i can actually move... Just to find out they are banning Perch over there to ... Yey ;- ) I haven't ever really considered moving to USA, i sort of have it made over here, where as i would have to start over if i move.B!
Arthur Posted December 9, 2014 Posted December 9, 2014 One of the very few ideas of Swede's that I disagree with is starting with KCl. The electrodes for chlorate withstand KCl to KClO3, but the electrodes for Chlorate to Perc are hard to find and expensive so giving them an easy life seems good to me.
MrB Posted December 9, 2014 Posted December 9, 2014 That pretty much boils down to one thing. Ease of use. Running one cell to go from NaCl to NaClO3, a second cell to go to NaClO4, and then make KClO4 from that, simply isn't "user friendly", and at least for me, that will put a large dent in how useful the process is.If the end product ends up costing twice as much just so i can go from KCl straight to KClO4, then so be it. It's a lot more "set it and forget it" to that. Best of all is, if i got as much right, you can run the system for long enough to get a substantial amount of KClO4, at which point you recover it, and top of the system with KCl, and off you go again.You don't need to run the system until it's "empty" and start over, you can just stay in some middle ground, and was away any thing that isn't KClO4 from your recovered end product. The "wash" is then just added to the working cell, and recovered. Yes. It seams more then likely that this will be more aggressive on the anode then the NaCl route, but also a lot easier to keep running. That said, there is so much about all of this i don't understand, so it might all just be a . (Link is not related to the topic)B!
Arthur Posted December 9, 2014 Posted December 9, 2014 In MY opinion only,KCl should give good potassium chlorate with ease, and it should be clean. BUT for Kperc I'd start with NaCl make chlorate in one cell, then make perc in another cell with a platinum electrode giving the expensive electrode a safer set of cell conditions to reduce erosion.. Dump KCl in later to ppt the perc out seems easy. But I was a process chemist in a factory for years. I suspect that the price of a platinum electrode will deter most people.
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