Arthur Posted March 9 Posted March 9 Computer power supplies are OK for small, proof of concept, cells BUT when trying for sustained operation at working currents between 2 and 50 amps only carefully chosen power supplies work well for long. The Meanwell brand on ebay has a few sizes of psu to look at. Having a DC welder could be interesting BUT you would need to do a lot of work to get control of the volts and current to suit this process. What is the continuous rating of the welder you are considering? Welders are probably the best example of design down to duty cycle. They are probably expected to run for 2 - 5% of the time you are welding, which is then defeated by the need to run a cell for 168 hours a week.
mx5kevin Posted March 10 Posted March 10 What are important in the power supply to have a safety fuse in it that melts if the circuit is overloaded. The are DC step down modules with volt/ampere display if one wants to be precise, and they are good for 12V car battery chargers. If someone using a fix 6V power supply will be OK without it. But without a measuring instrument, it is not possible to say the pair of electrodes is placed in the solution, how much it loads the system. Have to take into the maximum amperage a power supply can deliver, but you have to stay well below that because it will overload. The thickness of the wire, the surface and proximity of the electrodes, it depends how many amperes actually pass through during operation. Battery chargers have an electric fuse. In a 6V 4A car battery charger have a 4A fuse. It should not be loaded more than 2 amps, when the cell is running. In this setup if a 6V 6A car battery charger are used, but the same electrodes and wires remain, no more amperes will flow through the system. As the process progresses, less and less amperes pass through. When the NaCl solution are start the value that actually passes through the cell should be 2A in this calculation. In the NaClO3->NaCl04 setup this will be under 1A. The larger the electrodes, the larger the surface area, and they are close to each other the more amperes actually pass through the cell. But here you have to pay attention so that it remains below the power of the power supply. Car battery chargers have a built-in ammeter and a safety electrical fuse, the measuring instrument shows how long it can be loaded. Do not exceed 2 Amps in the case of a 4 Amp charger. If anything goes wrong, the fuse will blow. It is my own experience that you should not use any power supply under 4 amperes. A 70mm long 3mm thick 200 micron thick platinum electrode on a silver base 1.5 amps go through it whit a 10mm graphite cathode. And this is the minimum that is suitable for production.
mx5kevin Posted March 10 Posted March 10 (edited) I found a much more effective method than the KCl+NaClO4 for KClO4 production. KClO3+NaClO4 for KClO4 production using hot filtering are much more faster, cheaper. But it requires more experience. The method is electrode-friendly because perchlorate residue in a chlorate cell strongly erodes the anode, and chloride in the perchlorate cell are a big anode killer too. What to watch out for are the potassium, in the chlorate to perchlorate conversion it precipitates immediately at the anode in the form of potassium perchlorate. This is not a problem with platinum, but it causes deposits on lead dioxide. But since NaClO3 are highly soluble 105.7 g/100 mL (25 °C), a clean hot water bath will easily dissolve from the lead dioxide anode if the NaClO3 concentrated/filtered from the chlorate and later it was diluted back. The NaClO3 can be reused indefinitely to make NaClO4. And making KClO3 are much more faster than NaClO3. In a pH controlled cell, less hydrochloric acid is needed and less chlorine gas is released. And for pH controlling a plant infusion sett (Plant Life Support Drip) are excellent. Edited March 10 by mx5kevin
taiwanluthiers Posted March 20 Posted March 20 (edited) Sorry I didn't read the above replies. Most stick welder has a 50% duty cycle if you run them at maximum amp, most of that being around 250 amps. Unless you are making a very large cell you are not going to be running them at such a high amp, we're thinking 20-30 amps here. Most stick welder can do this at 100% duty cycle (most of them are rated to 100 amps at 100% duty cycle). Edited March 20 by taiwanluthiers
mx5kevin Posted September 11 Posted September 11 NaClO4+KClO3=KClO4+NaClO3 CN102807192A Potassium perchlorate production technology with zero wastewater discharge and products thereof. I ran into a few problems that seem to have been fixed. The first problem is to keep the chlorate in solution so that the perchlorate precipitates most efficiently. I calculated a 73g/l saturated KClO3 solution at room temperature what are calculated to the current NaClO4 cell size. First the NaClO4 cell with the solution are filtered from all insoluble impurities. Than in hot minimum 90°C cell solution dissolved the KClO3 and cooled down in the cell and filtered the KClO4. After this reaction the NaClO3 are converted back to NaClO4 which is very fast using electrolysis. The process can be repeated indefinitely, only sometimes the NaClO3 must be refilled. If this is repeated twice with the crystals, using as clear as possible NaClO4 the chlorate separates nicely from the perchlorate. The process does not require a procedure that causes unnecessary material loss. Based on the experiments so far, it is much better than a KCl+NaClO4 reaction especially for the price/value ratio. I found a big disadvantage is that potassium separates on the anode and therefore causes deposits in the perchlorate cell in the case of a lead dioxide. By cooling the cell solution to around 0°C, the potassium can be easily separated, but the problem is that if lead dioxide is used, there will be a KClO4 deposit on it. I recommend the method to those who prepare chlorates and perchlorates with a single platinum clad electrode. In the case of sodium, I found that it takes at least twice as much time to convert from chloride to chlorate as it does for potassium (with a single platinum). And converting NaClO3 to NaClO4 so much time than converting KCl to KClO3 (with a single platinum).
Arthur Posted September 11 Posted September 11 I once read (online!) a technical paper on the workings of the Pepcon plant. The electrolytes were sodium chloride based for the first process to chlorate and then the second process to perc.. Thus the most soluble salts were used to aid efficiency. Sodium products were then dosed with KCl to ppt out the K Chlorate or K perc. The electrolyte was thus returned to being a sodium chloride brine solution which could be directly returned to the first electro cell directly. While the startup solution was sodium chloride brine, the final product was precipitated out using potassium chloride. The oxygen that makes perc from chloride is taken from the water solvent, it's hydrogen being lost by gassing to the atmosphere. 1
mx5kevin Posted September 12 Posted September 12 12 hours ago, Arthur said: I once read (online!) a technical paper on the workings of the Pepcon plant. The electrolytes were sodium chloride based for the first process to chlorate and then the second process to perc.. Thus the most soluble salts were used to aid efficiency. Sodium products were then dosed with KCl to ppt out the K Chlorate or K perc. The electrolyte was thus returned to being a sodium chloride brine solution which could be directly returned to the first electro cell directly. While the startup solution was sodium chloride brine, the final product was precipitated out using potassium chloride. The oxygen that makes perc from chloride is taken from the water solvent, it's hydrogen being lost by gassing to the atmosphere. With a combination of MMO and PbO2 the recovered NaCl from KCl+NaClO4 reaction are faster and better, there it can be less than 1 week. With MMO NaClO3 production are much more faster. But there is also a problem that the chloride is contaminated with a certain amount of perchlorate. This multiplies the erosive effects in the solution. The MMO anode is attacked by perchlorate. If platinum are used for chlorate production with NaCl to NaClO3 the production takes at least twice as much time than making KClO3 from KCl. The third problem if the NaCl are not recovered significantly increases costs for larger doses, and pH regulation also requires more hydrochloric acid if chlorate production are slow. Neutralizing perchlorate is a bit complicated before the electrolysis, not sure if it's worth it. A longer-term feedback from others would be good about how well it wears, for example, an MMO anode, or rather it shortens its lifespan, but it is not such a big problem. It is clearly written in the industry that it shortens its lifespan in such cases. But I haven't found any methods what they are writing to cheaply neutralizing the remaining perchlorate simply in a large batch and good for us too. Those who use a combination of MMO and PbO2 and recycled the NaCl after the KCl+NaClO4 reaction they should give feedback in amateur setups on how much of a problem this is in the long term. And that kinds of feedback is hard to find in amateur circles.
eb666 Posted September 12 Posted September 12 Quote from elsewhere: An AC welder is a good supply to use for a cell but the output MUST be rectified before applying it to the cell. A DC welder will do too. The welder will be a constant current generator but its lowest current setting may be too big for your set up (size of Anode and cell volume). There is also the disadvantage of the welders high open circuit Voltage. When you disconnect the welder it's output voltage will rise to maybe 80V. If, when your cell is running, one of the connections going to the Anode or Cathode gets corroded the voltage will rise across this bad connection as the welder forces in the constant current. This will lead to the connection failing by becoming red hot. This may permanently damage your Anode or perhaps cause a fire/explosion. A welder makes a good supply for an established cell and setup that has good connections, but it is a bad supply for experimenting with The above is referring to an old type 'buzz box' (american term) welder. It simply consists of a transformer followed by an inductor to limit the current (or the inductor may be somehow part of the transformer). I dont know about the modern switched mode power supply welders. The simple cheap ones for stick welding and tig welding have a switch for going from TIG to MM arc (stick welding). I presume the TIG output is DC and the stick output is AC (guess). You will still have the large open(ing) circuit output voltage problem as stated above. It may redden/damage/explode the cell if a connection gets bad. Some of the TIG outputs have a very high Voltage (high impedence, only some microamps will flow) superimposed on the line to facilatate non-contact arc starting. The duty rating will vary as you put the current up. At full current they may be (say) 30%. At a smaller current they may be 100%. Look at the nameplate. The original poster of this thread was saying that he went from K Chloride to K Chlorate to K Perk. Thats very very labour saving if you want to keep Na OUT (for colour etc). He also give an explanation of how Ca chloride is helping to keep the pH of the cell around neutral. CaOH deposites and effectively removes OH- (OH minus) ions from the system. Is this a correct or plausable explanation? Has anyone here tried to use Ca chloride to help with pH. HCl can be difficult to get for some people assuming they want to bother with pH control. Regarding the silver clad with Platinum anode. I presume the silver sticks out of one end of the anode or is the whole piece of silver coated (clad) with Pt? To put it another way, is there a 'top' and 'bottom' to the anode? If there is a 'top' (the end where the silver protrudes out from the Pt skin/cladding). Do you have this exposed piece of silver outside the cell or is it inside the cell in the airspace between the cell liquid and the lid? What I am trying to find out is how much of the Pt area is wasted as the current runner coming from outside the cell (where the electrical connection is) to the surface of the cell liquid? Silver is remarkabely resistant to the spray. I remember (back in the day) that you painted silver onto LD anodes for a connection before adding copper connections (no Ti substrate). The silver oxide that inevitably forms, is conductive. Quote: "My specialty is potassium perchlorate. I've been making it for 15 years. For a 0,5l cell a 70mm long 3mm wide silver rod what is fully coated with 0,2mm thick pure platinum so that they are not attacked by chemicals a choice for life for chlorate and perchlorate production." Feel free to correct my maths but I make that (a rod) an area of: 7cm long by 0.3cm dia = pi r^2 * L = 3.142 * 0.15^2 * 7 = 0.5CM^2 usable surface area. (Assuming all of Pt is in the cell solution) If you run that hard you would get 0.5 Amps into the cell. Amount of Pt metal is: 0.5 * 0.02cm * 21.4 (density of Pt) = 0.214 grams Pt. The one gram platinum bullion bar + titanium current runner is the proper paupers anode (never mind yur auld silver!!) You will probably pay less for the one gram of Pt bullion and when hammered to double it's surface area (approx. 5cm^2) you could run at close to 3 amps at a similar current density to the above anode. The Ti current runner can be as long as you like. Pt is quite cheap(ish) at the moment. It appears to be falling in price. EB 1
mx5kevin Posted September 12 Posted September 12 (edited) 4 hours ago, eb666 said: Quote from elsewhere: An AC welder is a good supply to use for a cell but the output MUST be rectified before applying it to the cell. A DC welder will do too. The welder will be a constant current generator but its lowest current setting may be too big for your set up (size of Anode and cell volume). There is also the disadvantage of the welders high open circuit Voltage. When you disconnect the welder it's output voltage will rise to maybe 80V. If, when your cell is running, one of the connections going to the Anode or Cathode gets corroded the voltage will rise across this bad connection as the welder forces in the constant current. This will lead to the connection failing by becoming red hot. This may permanently damage your Anode or perhaps cause a fire/explosion. A welder makes a good supply for an established cell and setup that has good connections, but it is a bad supply for experimenting with The above is referring to an old type 'buzz box' (american term) welder. It simply consists of a transformer followed by an inductor to limit the current (or the inductor may be somehow part of the transformer). I dont know about the modern switched mode power supply welders. The simple cheap ones for stick welding and tig welding have a switch for going from TIG to MM arc (stick welding). I presume the TIG output is DC and the stick output is AC (guess). You will still have the large open(ing) circuit output voltage problem as stated above. It may redden/damage/explode the cell if a connection gets bad. Some of the TIG outputs have a very high Voltage (high impedence, only some microamps will flow) superimposed on the line to facilatate non-contact arc starting. The duty rating will vary as you put the current up. At full current they may be (say) 30%. At a smaller current they may be 100%. Look at the nameplate. The original poster of this thread was saying that he went from K Chloride to K Chlorate to K Perk. Thats very very labour saving if you want to keep Na OUT (for colour etc). He also give an explanation of how Ca chloride is helping to keep the pH of the cell around neutral. CaOH deposites and effectively removes OH- (OH minus) ions from the system. Is this a correct or plausable explanation? Has anyone here tried to use Ca chloride to help with pH. HCl can be difficult to get for some people assuming they want to bother with pH control. Regarding the silver clad with Platinum anode. I presume the silver sticks out of one end of the anode or is the whole piece of silver coated (clad) with Pt? To put it another way, is there a 'top' and 'bottom' to the anode? If there is a 'top' (the end where the silver protrudes out from the Pt skin/cladding). Do you have this exposed piece of silver outside the cell or is it inside the cell in the airspace between the cell liquid and the lid? What I am trying to find out is how much of the Pt area is wasted as the current runner coming from outside the cell (where the electrical connection is) to the surface of the cell liquid? Silver is remarkabely resistant to the spray. I remember (back in the day) that you painted silver onto LD anodes for a connection before adding copper connections (no Ti substrate). The silver oxide that inevitably forms, is conductive. Quote: "My specialty is potassium perchlorate. I've been making it for 15 years. For a 0,5l cell a 70mm long 3mm wide silver rod what is fully coated with 0,2mm thick pure platinum so that they are not attacked by chemicals a choice for life for chlorate and perchlorate production." Feel free to correct my maths but I make that (a rod) an area of: 7cm long by 0.3cm dia = pi r^2 * L = 3.142 * 0.15^2 * 7 = 0.5CM^2 usable surface area. (Assuming all of Pt is in the cell solution) If you run that hard you would get 0.5 Amps into the cell. Amount of Pt metal is: 0.5 * 0.02cm * 21.4 (density of Pt) = 0.214 grams Pt. The one gram platinum bullion bar + titanium current runner is the proper paupers anode (never mind yur auld silver!!) You will probably pay less for the one gram of Pt bullion and when hammered to double it's surface area (approx. 5cm^2) you could run at close to 3 amps at a similar current density to the above anode. The Ti current runner can be as long as you like. Pt is quite cheap(ish) at the moment. It appears to be falling in price. EB The platinum anode: See here my blog: The 70mmx3mm silverx0,2mm pure platinum it surrounds the platinum from all sides, there is no free silver part so that the chemicals cannot attack it. Yes the whole piece of silver coated (clad) with Pt, the 2 ends of the rod precisely closed with platinum. In my blog, there is a picture, a blueprint, and it is shown how it is producing in a 400ml NaClO4 setup using a 700ml glass jar cell (with a video). 2 week the NaClO3 from NaCl+1week the NaClO4, 1 week the KClO3 from KCl in this setup using a non precise pH control. 1,5A can also pass through it, in general, 1A actually passes through it (this is typical during the running time of the cell), 0,5A when the cell slows down at the end process. This anode required a 6V 4A power supply, if someone uses less than this, they can easily overload the power supply. Calcium Chloride: This is nonsense, it sticks to the cathode and pollutes the cell, in professional circles it is mentioned that the calcium content should be as low as possible. I don't recommend it to anyone. Larger Platinum anode: The 0.2mm (200micron) platinum layer is highly recommended. Silver is the best electrical conductor, it is not worth saving on it. It's cheap compared to platinum, it is considered cheap in such a small size . If someone has money, they can make a 4mm silver base and a slightly longer rod, but it will be at least double as expensive. If you want example a 0,2mm thick 200 micron pure platinum on a 5mmx80mm silver base it is not worth planning anything bigger than that. It would be more expensive than the price of a large MMO and PbO2 combination, it produces much more slowly, but this platinum worth much more in the long term. Slightly larger sizes are significantly more expensive for such an thicker platinum electrode. Don't expect it to be cheap for you. Don't even plan for a larger size because it would be prohibitively expensive for this purpose. To the extent that you want a poorly conductive titanium base or a cheaper solution, why risk paying a lot of money for platinum, and the base is not a good conductor and will not work properly? For this type of electrode, if it is not silver, copper will be thin niobium and then platinum, but titanium is not suitable for this type of electrode because it is a poor electrical conductor. Platinum electrodes of a few microns coated to a titanium base are useless. I got the small electrode in a similar price category, and it has lasted for almost 10-15 years. Platinized titanium anodes, it may not even last a year. Instead of platinized titanium, it is worth investing in an MMO+PbO2 combination (MMO+PbO2 combination, it won't last for years). But if you have to replace something like that, it's a lot of money. It took almost 5 years for me to i get back the invested money in it with all the equipment. The beaker breaks, the hotplate is ruined, all extra costs. If the tools is not used, it will break down while standing, even smaller things wear into these cells over time. What is worth it is the cyclical production, producing larger portions over 5kg, what are enough for a longer period of time. And this also includes the fact that you have to get the routine for this. Because someone has done it twice successfully, it doesn't mean they do it routinely and efficiently. KClO4 from KClO3 electrolysis: It is terribly slow if someone were to try electrolysis a pure KClO3 solution to make KClO4. At the end product, there can be no difference between the product and the method by which it was made. Using the NaCl setup, the user make at least 20X the amount in the same amount of time. And if it's done well, there won't be any sodium or other contamination in it that would affect the color or anything else. KClO4 is the easiest perchlorate to clean with recrystallization. If it is crystallized twice in more water and the crystals are rinsed with cold water during filtration, if the chlorates are previously neutralized, a product that is purer than the factory technical quality is obtained. It will be a product with a purity of around minimum 99,5-maximum 99,7%. This has no effect on compositions. Edited September 12 by mx5kevin
eb666 Posted September 12 Posted September 12 I got the formula for area of rod completely wrong. I was using pi * r^2 instead of 2Pi * r. Surface area of rod is 6.6 cm giving 3.3 Amps at a 500mA per square cm. Total Pt is about 3 grams. Hope I am right this time. Density of Pt is 22.4 grams per cm squared How do you connect the Pt anode to the power supply. Do you run a titanium rod (or what do you use) between the outside of the cell and the Pt anode in the electrolyte. Is ALL of the anode submerged? What does the anode cost at todays price? (approx.) Is there a link to a picture of the anode being used. Quote; "It will be a product with a purity of around minimum 99,5-maximum 99,7%. This has no effect on compositions." 0.1% will have a washing out effect in your 'delicate blues' etc when used for coloured compositions. (Or so I believe) I don't make fireworks so I will leave it to the experts. 0.5% Na in K compositons I would imagine would be very noticable as sodium has a very powerfull ability to produce yellow when burned. EB
mx5kevin Posted September 13 Posted September 13 (edited) Quote Is there a link to a picture of the anode being used. Links: The homemade chlorate and perchlorate project Hungarian blog: https://mx5-kevin.blogspot.com (here have a picture and a blueprint from the platinum anode) Video: Make potassium perchlorate KClO4 from sodium perchlorate NaClO4 with electrolysis Quote How do you connect the Pt anode to the power supply. Do you run a titanium rod (or what do you use) between the outside of the cell and the Pt anode in the electrolyte. Is ALL of the anode submerged? I use a simple champagne cork. The copper wire, some plastic foil, and silicone sealant go on the electrode. And some hot glue. Ideally, the electrode is inserted at the bottom of the cell as deep as possible, so that the chlorine in the solution can travel as far as possible before reaching the top of the cell. I pass the gases formed at the anode through the cathode. If this cannot be solved, I introduce the electrodes from above. The copper connection must not be in the solution. Who can make by self a more advanced setup a rubber seal is useful. Quote I got the formula for area of rod completely wrong. I was using pi * r^2 instead of 2Pi * r. Surface area of rod is 6.6 cm giving 3.3 Amps at a 500mA per square cm. Total Pt is about 3 grams. Hope I am right this time. Density of Pt is 22.4 grams per cm squared My electrode is around it maybe 3g the Pt. If you want a 5mm electrode feel free to count 8 grams Pt. Your calculations are probably still not good. what are you counting on? Minimum more than 130 USD if you want a 3x70mm silver basex0,2mm pure platinum. Designing a size below this is unsuitable for production. If you want bigger a 5mm 300 USD above and this is a cheap calculation. You can count up to 600 USD price, if you want to go through 3A for you and 5mm size. The 70mm long should be, don't shorten this. There you need a 6V 8A power supply (car battery charger are cheap). You give one of the specialized manufacturers for laboratory platinum anodes exactly what you want, and you ask for a quote from several places. Forget about other designs such as mesh, wire, because you cannot create a suitable surface with them. Quote "It will be a product with a purity of around minimum 99,5-maximum 99,7%. This has no effect on compositions." 0.1% will have a washing out effect in your 'delicate blues' etc when used for coloured compositions. (Or so I believe) I don't make fireworks so I will leave it to the experts. 0.5% Na in K compositons I would imagine would be very noticable as sodium has a very powerfull ability to produce yellow when burned. You can't experience anything like that. For blue, I use potassium perchlorate, which is made from sodium perchlorate, and for many others, the control substance was pharmacopoeial quality KClO4 obtained from a pharmacy. Mixed with hydrochloric acid or in compositions, there is no difference between the two. Very sensitive and expensive laboratory equipment could only be used to show exactly what other impurities it contains. Sulfur, metal powders, colored compositions, and storage have no effect on these. If someone has such a problem, they are doing a lousy job. We are talking about an almost analytical quality in homemade KClO4 (what is sold in pyroshops is less pure than homemade). If it has been crystallized once more in distilled water, it has analytical quality, but not pharmacopoeial quality. Edited September 13 by mx5kevin
eb666 Posted September 13 Posted September 13 Thanks for the picture. The Pt is black. I presume it was shiney at the start. Is the black deposits caused by impurities? You could carry current to the Pt anode if you wish using two pieces of titanium instead of the champaign cork + rubber. You might end up with more Pt exposed to the solution which means you could run more current from the anode. Something similar to what is in the attached picture that uses a one gram bullion bar. The Pt is squeezed between two pieces of Ti. It works good. Perhaps I am obsessing over purity of product. eb
mx5kevin Posted September 13 Posted September 13 (edited) 2 hours ago, eb666 said: The Pt is black. I presume it was shiney at the start. Is the black deposits caused by impurities? You could carry current to the Pt anode if you wish using two pieces of titanium instead of the champaign cork + rubber. You might end up with more Pt exposed to the solution which means you could run more current from the anode. Something similar to what is in the attached picture that uses a one gram bullion bar. The Pt is squeezed between two pieces of Ti. It works good. Perhaps I am obsessing over purity of product. Do not allow any inappropriate metal to enter the atmosphere of the solution. My cathode is graphite, the top of the cell is plastic. No matter how much time I run the cell, foreign metal that dissolves does not enter. Little graphite, minimal iron oxide in KCl and insoluble dirt can be removed by simple filtration. The KClO3 washed with ice cold water, dissolved in hot water and filtered from insoluble contamination. The crystals and the solution are completely clear. I don't have any dirt on the anode. In the case of NaCl there are no crystals in the solution, all insoluble impurities settle and it is even easier to filter. If the solution becomes colored or something dissolves, the solution dissolves something inside the cell. Always use under the beaker Wire Gauze Heat Shield Ceramic Center. Protect the Hot Plate with aluminum foil (one should be bought for this purpose). Run outdoor the cell, buy a separate cable of a few meters. You need a M3 chlorine protection mask and airtight goggles, use rubber gloves. The process gives itself when and how to clean. Continuously producing for a longer period of time, before a device breaks down, is much more worthwhile than producing a few kilos and then stopping the production, then producing again later when it runs out. The previously used cell solution must not be placed in the stainless steel pan. Or heating in stainless steel pan acidic solution, heating KCl, NaCl, NaClO3, NaClO4 crystals in it. If pure platinum is used, there is no need to accurately measure the pH value and buy expensive equipment separately. If you buy a pH paper, there's a good chance it will bleach everything (and diluting and boiling the solution will not help). Calibrating a digital pH meter is expensive and breaks down over time. I spent a lot of unnecessary extra money on things like this. No need for expensive chlorate and perchlorate tests. A simple methyline blue/sugar test (if you need NaClO3), a simple heat probe if you need NaClO4, if you can melt it on a gas stove, it's not ready yet. Whatever you can recover wastewater in the solution. But it is natural that the product must be purified by recrystallization where there is a greater loss. You should never skimp on the end product purity! These small mistakes increased the costs unnecessarily to the same amount as the total basic equipment. Edited September 13 by mx5kevin
eb666 Posted September 13 Posted September 13 To quote: "........clear. I don't have any dirt on the anode. In the case...... " In the picture of your anode the platinum anode is a black colour. Was it a black colour when it was new or was it shiney white (like platinum metal)? I think I am perhaps looking at the graphite cathode and the (shiney) Pt anode is the rod behind the black cathode.
mx5kevin Posted September 13 Posted September 13 (edited) 2 hours ago, eb666 said: To quote: "........clear. I don't have any dirt on the anode. In the case...... " In the picture of your anode the platinum anode is a black colour. Was it a black colour when it was new or was it shiney white (like platinum metal)? I think I am perhaps looking at the graphite cathode and the (shiney) Pt anode is the rod behind the black cathode. The big one is a graphite cathode, I recommend 10 mm thick (made from a copper coated carbon welding rod). It had a thin copper layer that was simply pulled off like peeling an onion. In the picture this is 6mm, possible to buy 8mm size too. The smaller second bright is the platinum anode 70x3mm silver x0,2mm (200micron pure platinum), closing the entire anode at both ends with platinum. Making an platinum anode as big as a graphite using a silver base or thinner platinum like 100 micron rod would be prohibitive. There is no deposit on the platinum anode, just a little water. The cathode has some natural salt deposits from the cell (not contamination). The champagne corks should be introduced from the outside at the top, and not from the inside as I did. To the plastic pipe some hot glue. The platinum anode is more than ten years old and has been in perfect condition with regular use ever since. Used for KClO3, NaClO3, NaClO4, expriments like: KClO4 from KClO3, experimental perchloric acid. It is not only good for chlorates and perchlorates, but for all types of other products, experiments that require platinum, and it does not damage the electrode. The jar are a 700ml glass jar with a plastic top cup. Edited September 13 by mx5kevin
mx5kevin Posted September 14 Posted September 14 (edited) 23 hours ago, eb666 said: Something similar to what is in the attached picture that uses a one gram bullion bar. The Pt is squeezed between two pieces of Ti. It works good. It is an interesting assembly, because if including the screw and washer it is not pure titanium and does not become non-conductive in the solution, this assembly would be eroded and dissolved by the solution, especially at the anode part. I saw another pictures of your anode. I see here the Specifications. Quote The cathode is bent around the Pt bar. It is hard to see in both diagram and picture. The bar measures 14.7mm x 8.9mm x 0.36mm giving a usable surface area of about 2.6 cm squared. If used at 400mA per square cm this gives a one amp anode. A lot smaller than I first guessed! Platinum purchased this way (one gram bars) is approx. twice the price of spot. I thought it was cheaper. We shall soldier on. The anode will last a very long time imo. eb This is almost the same 1 Amp as my anode, if it works well for you it is not worth replacing it. Purity is important, because there is high-purity platinum for laboratory purposes. However, for example, what is made of pure platinum as a sheet or mesh, wire is not good for us because it cannot withstand more amperes, they are so thin that they would melt even immediately, or it gradually corrodes due to the too small surface area. I have heard of cases where someone bought platinum with such a small surface that it was completely unsuitable for production. For the production of chlorate or perchlorate, and to withstand the appropriate amperes, a suitable stable surface is required. This can be ensured in cylindrical form on a very good electrically conductive base that is stable and hard. There are several types of these bases which is coated with platinum, but they are limited in what they can be. It is not advisable to buy such things from Ebay and similar marketplaces, only from a specialized manufacturer or distributor. You were lucky that it was real platinum and that it worked with it. If you want a slightly larger electrode, the price increases drastically. What I bought electrode 70mmx3mm silver base with 0,2mm pure platinum covering the entire silver surface the total price of this is equivalent to 4g of platinum price. But this platinum used for pure laboratory purposes. My setup: My electrode parameters: 3x70mm silver rod x0.2mm platinum, the entire rod is coated with platinum. It cannot be produced with a weaker electrode than this! Summary: Silver weight: approximately 5.18 grams Platinum weight: approximately 3.05 grams Required a 6V 4A power supply Maximum size: 5x70mm silver rod x0.2mm platinum, the entire rod is coated with platinum Summary: Silver weight: approximately 14.4 grams Platinum weight: approximately 4.94 grams Required a 6V 8A power supply It is not worth investing in anything more serious than the latter 5x70mm silver rod x0.2mm platinum electrode. I made more accurate calculations, the calculations seem to match the price I bought. In terms of price, the second electrode is also expensive but affordable. In my opinion, it is not worth planning a size larger than this. The second electrode will cost almost double the price of the first. But this will also be reflected in the production speed. About 250 USD I think it can be done the second one. In the past, when I asked for a quote, they said something like this. Converted to the old price, the smaller one I bought is now converted total price was 130 USD. Now I looked out of curiosity and the most expensive 30x30x0.2mm solid pure platinum sheet with a long ceramic stem was 700 USD, but on a dangerously small surface the electrode is connected to the ceramic. Now, surprisingly, when I had it done a long time ago, the platinum is at a similar price. Edited September 14 by mx5kevin
mx5kevin Posted October 14 Posted October 14 (edited) KClO3+NaClO4=KClO4+NaClO3 research, test results 5l 5000ml cell (original cell was 400-2000ml). Exceeding the original 400ml cell capacity many times over 10X. Used cathode 10mmx150mm carbon rod, used anode 70mmx3mm pure platinum on a silver base Power supply 6V 4A car battery charger Cell average temperature 20°C (operates outdoors in winter and summer) NaCl->NaClO4 direct conversion in pH controlled cell: The current Amps was the half of the KCl->KClO3 cell, and the run time was multiplied (completed the process after more than 5 months of running the NaClO4 in a 5000ml cell). The running time in a 400ml cell was 3 week. KCl->KClO3 in pH controlled cell: Less than 1 month the conversion are ready in a 5000ml cell. In a 400ml cell this was 1 week. The current amp was double what passed through in the cell stable way compared the NaClO4 version (average 1A passed through the cell). When the solution are recovered this was speed up the process from 4 week to 2 week. The KCl+NaClO4=KClO4+NaCl in this 5000ml setup are not ideal and too slow. In the 400-2000ml setup this method is tolerated. The remaining perchlorate within the chlorate cell significantly strengthens the erosion processes. I tested this by adding less insulated copper on the cathode and anode, the erosion rate increased significantly. In the another setup the chlorate cell are not contaminated with perchlorate, and the perchlorate cell not contaminated with large amount of chloride. And this is ideal for platinum. The KClO3+NaClO4=KClO4+NaClO3 conversion: Used cell solution under 750g/l NaClO4 (contaminated with NaClO3) directly from the cell. And 513g/l KClO3 solution. In the first experiment in the 750g/l NaClO4 directly from the cell i tried dissolving the KClO3 crystals directly at 100°C more than 500g KClO3 crystals. The result is that it can be dissolved, but compared to pure water, it is very difficult to dissolve when hot, and it takes too much time and work to dissolve the crystals in this way. This method was not effective, however, the obtained result proves that, compared to pure water, approximately quarter as much potassium remains dissolved at room temperature. In the next setup the 750g/l NaClO4 and 513g/l KClO3 heated to 90°C. And slowly added to the KClO3 solution to the NaClO4. KClO4 crystals precipitated immediately. The amount of NaClO4 in the solution that can be traced in the process, because when it runs out, the precipitation of white crystals ceases. This is good news because in this way it is not possible to significantly overdose the KClO3 and the solution can be cooled at room temperature without too much KClO3 being released. When the solution are cooled down the crystals mainly contained KClO4 and KClO3 was minimally precipitated. After the filtration the NaClO3 are converted back to NaClO4. Run time 1 week. The KClO4 crystals are boiled from the first reaction (not dissolved) in the 750g/l NaClO4 cell solution without adding external water, using a beaker to minimized the KClO3 in the crystals and the solution are cooled down to room temperature. The crystals will not dissolved in the hot boiling cell solution, but their size will increase somewhat and their chlorate content will decrease. After this the crystals are washed mixed in ice cold water and filtered. Chlorate can be detected in the resulting product, but this is already the amount what can easy way can terminated using the K or Na metabisulfite K2S2O5+HCl+Boiling method. Based on the results obtained, the method is effective for production. Used reaction setup 1 NaClO4 cell solution for 1 KClO3 cell solution from the same sized cell. In the recovery the sulfide, sulfate was neutralized using calcium chloride. Disadvantages: The first disadvantage is that lead dioxide anode cannot be used for the method. KClO4 is formed at the anode. A second disadvantage is that a lot of water is needed to dissolve KClO4 compared with NaClO4 when the chlorate are destroyed. Result: Based on the experiments, the method can be used well for continuous large-scale production at home. By increasing the cell size by 10X, NaClO4 from NaCl production is too long but this is 1X required to make, but the NaClO4 from NaClO3 conversion well tolerated and fast. I perfect the description the method in my blog, because not possible to do it here on the forum the unlimited subsequent editing of the content: Edited October 14 by mx5kevin
mx5kevin Posted October 18 Posted October 18 I would like to describe one important thing. Did someone write calcium chloride for pH control, it won't work. It only contaminates the cell, settles at the bottom and sticks to the electrode. This idea comes from a YouTuber and is not supported by any professional documentation. I tried to see if it is possible to remove potassium metabisulfite and sulfate from a KClO4 or NaClO4 solution after neutralizing the chlorate in the presence of hydrochloric acid. Nothing precipitates in a strongly acidic solution. Metabisulfite and sulfate cannot be removed in such a simple way. If someone wants to use the NaCl solution after a KCl+NaClO4 solution, is forced to neutralize the chlorate with KClO4. The metabisulphite solution can be used several times, 3X without any problems. The boiled, saturated KClO4 solution does not need to be boiled very much, the KClO4 separates nicely when it cools down to room temperature. It is definitely worth returning the sodium salts to the process because it noticeably reduces costs for larger batches. The raw materials used for KClO3 and KClO4 production are: KCl, NaCl, HCl, K2S2O5. Hydrochloric acid is the most expensive and runs out quickly. It is worth buying a 5 liter 30% HCl package from a cheaper place, if someone makes larger quantities. Which has paid off many times over and is very cheap Wire Gauze with Ceramic Center under the glass Beaker what need to aid in the distribution of heat. And protecting the Hot Plate with aluminum foil, because these oxidizers they corrode metals! In a stainless steal never boil the cell solution or acidic solution. Or heat in it KCl, NaCl, NaClO3 and NaClO4. KClO4, KClO3 solutions can be boiled in it dissolved in pure water. And KClO3 and KClO4 crystals be dried in stainless steel pan in small portions on gas stove. What is also very important is to return as many raw materials as possible to the process. It is not a cheap and time-consuming thing that requires patience.
Recommended Posts