Sodium Perchlorate using a diaphragm cell

[AlteredMatter]

Have you ever noticed that in a lot of information about perchlorate preparation that it says " Graphite can be used with a cell with a diaphragm", according to some patent. I've actually tried this and got a positive result for perchlorate using a methylene blue solution after making the testing solution alkaline with NaOH. However, when I precipitate it out using potassium chloride, the positive test disappears! Theoretically, in a diaphragm cell the anode and cathode products do react, but they travel through the diaphragm due to electrodialysis. The sodium hydroxide in the cathode compartment is attracted to the chloric/perchloric acid in the anode compartment so it travels through the barrier and reacts to form sodium perchlorate. When I got a positive result, starting with sodium chlorate it took about 9 hours at 6V 6A using a battery charger. One mole of sodium chlorate divided in half between the anode and cathode compartment. I was using a terra cotta clay pot as a diaphragm and it seems to do the job well. Has anyone else ever tried this?

[Scorpion812]

Wow, this sounds like a really fun, cheap, easy and fast way, except, if i heard it right, it uses perchloric/chloric acid, which is pretty dangerous and hard to get by. But about that NaClO4, try just running it longer and then test it again, or just try to boil off the water instead of DD with KCl

[mx5kevin]

The topic deserves a more thorough research. In principle, it would work with the perchlorate synthesis with electrolysis without platinum or PbO2 anode. Patent US1279593A says with graphite or Si using a diaphragm cell possible to make perchlorate. The are SiC and Glassy Carbon which did not exist long ago. Glassy carbon crucible 10cm long and 2,4cm outside diameter, trade name SIGRADUR used sucessful for a chlorate cell. There is slower wear but the solution is clear. Using a NaClO4 KClO3 concentrated hot solutions double-displacement reaction and hot filtering the KClO4 can be easily separated from the chlorate. It takes a lot more time than with Pt, PbO2. Need a cheap, easily available electrode. It is also worth combining with an ozone generator. Using some sulfuric acid. Must check US 2858188, and DTIC AD0016814: Research on the Exploration of Methods to Produce Chlorates and Perchlorates by Means Other than Electrolytic documents. By keeping the solution hot, cold and the resulting chloric acid keeping above and under 40%, bubbling ozone, and not can make a lot of difference. There are cheaper ozone generators. There is no guarantee that it really works.

 

The thermal decomposition the problem with is under degrees 400°C does not work. And using a simple gas stove this temperature cannot be reached. An inert ceramic that can tolerate high temperatures is required. Need a precisely controlled temperature over a long period of time like a charcoal mini grill with thermometer. Guaranteed to work, just complicated.

 

Using US 2853362A - Process of producing perchlorates from chlorates (without electrolysis or thermal decomposition) guaranteed to work with high yield. Na2CO3+PbSO4=PbCO3+Na2SO4, Na2CO3+PBCO3+Cl2=PBO2+2NaCl+2CO2 Lead dioxide is recoverable, and sulfuric acid also recoverable from sodium sulfate using HCl. This is a cheaper way with high yield results without electrolysis or thermal decomposition. Guaranteed to work, just complicated. But everything that is not electrolysis here costs minimum double or many times more.

 

Which is an alternative boiling chlorate with 50% HNO3 the resoult are 30% yield. Extract the perchlorate, HNO3, H2SO4 back are possible but not cheap. The yield is low and the method is costly.

 

No one has developed effective home-made techniques for these methods. And these days, these alternative techniques are needed more than ever. More professional chemists like NurdRage who have equipment such experiments should be jointly supported in order to document them in detail on video. It would be easier for everyone than if we experimented with it separately. Those who achieve results for the community should be supported, until there is a developed technique everyone is throwing away money. There are methods that would be good for us, but for modern industry is not worth dealing with it. There are descriptions of the methods in old documents, but now there are more modern tools for it that were not available then. However, modern industry will no longer deal with these.

Edited June 4, 2023 by mx5kevin

[mx5kevin]

This reaction requires a membrane that prevents the mixing of the anode and cathode spaces. A multiple of the operating time should be calculated compared to a platinum or lead dioxide. It is unnecessary to try to extract the perchlorate with potassium chloride. If hot and concentrated NaClO3, NaClO4 solution are used with hot concentrated KClO3, which fall out crystals can be KClO4. If the anode and cathode spaces are mixed, the reaction is guaranteed not to work. Membrane cell requires stable chlorate with minimal chloride concentration, or the whole thing will be a chlorine generator. It must not be forgotten that glassy carbon did not exist in the past when these patents were made. Modern industry is not even worth dealing with it. Different types of glassy carbon are used for modeling and many other things, many varieties can be purchased cheaply, but they may not be suitable. All electrode will fall apart in this setup. It is possible that the method will work effectively only with the introduction of ozone, this will erode the anode even more faster. In order to work with ozone, it is necessary to generate different oxides of chlorine from the chlorate. And this is a big anode killer. The process works perchlorate can detected, we know the reaction is slow, and can combine with the US 2858188 production of perchlorates from corresponding chlorates by reaction in acid solution with ozone patent which is an effective method. A cheap ozone generator and an electrode that is cheaply available to everyone should be found. If graphite, SiC, Si, Glassy carbon none of them would work, then it's not worth bothering with this anymore because it's all nonsense. The magnetite remains (but I think it falls apart too quickly in this setup), and homemade lead dioxide but frankly it seems an costly and hopeless undertaking, but it is worth experimenting with. It is not a stupid thing that someone invented by himself, but it is supported by scientific documents that it is worth dealing with.

Edited June 4, 2023 by mx5kevin

[Arthur]

Most method in use professionally/industrially are chosen for giving economic electrodes an easy life. Platinum may be scary expensive but at a loss rate of milligrams per ton of perc the cost was little. Exotic electrodes are expensive but this is OK if they are permanent.

[mx5kevin]

Making potassium perchlorate without lead dioxide, platinum, electrolysis, and complicated chemicals or extreme heating more than 400°C. The first method I would try are the US2858188A patent. Nothing else is needed only electricity. Just need 60% perchloric acid (12-15% NaClO3 can be added), a ozone generator and need to keep the temperature 80 to 85°C. The perchloric acid are recoverable in the process. The whole thing is that chlorate is added to the warm perchloric acid to form chlorine dioxide and ozone is bubbled to make perchlorate. From sulfuric acid or nitric acid equally good for the process and perchloric acid can be prepared with these from sodium chlorate. This is the method available to everyone. An ozone generator is needed instead of a platinum or lead dioxide electrode.