Potassium Chlorate Synthesis Two Ways
Vložit
- čas přidán 12. 01. 2024
- In this video I demonstrate two ways to make the powerful oxidizer Potassium Chlorate.
Technically there is a third method introducing pure chlorine to potassium hydroxide, but it sucks.
Regardless, stay safe and don't try anything you see here without a lot of experience or formal training as this video involves the use of highly toxic, mutagenic chemicals, potentially explosive mixtures, hazardous voltage, corrosive acids.. you get the idea
#chemistry #science #hydrogen #gas #elements #fire #chemical #industury #color
That’s a BIG cathode. Generally it should be smaller than your anode to cut down on reduction of the chlorate at the anode. Things can get pretty complicated when you’re trying to get maximum efficiency from a chlorate or perchlorate cell with different electrode materials, ph control and catalysts added to the cell liquor. The cool thing is that even with a setup that’s far from ideal you’ll still produce a good amount of chlorate by running the cell for a while longer. Adding a little calcium chloride or magnesium chloride or sulfate is a good method for passive ph control. Great job, electrochemistry is always fun to watch!
It did feel like a comically large cathode lol, actually surprised everything turned out as well as it did all things considered. As you said the chlorate is pretty stable so once its produced it kinda just hangs around (unless you further oxidize it to perchlorate), and so even with a stupidly low efficiency you should eventually get a good amount.
I'm guessing the mechanism of passive pH control is that the hydroxide is removed as an insoluble precipitate? Thats clever, I'd have never thought of that.
One question I have since you clearly seem to have more experience with electrolysis: I was considering using dithionite or something similar to reduce the chromate when this was finished so this would all be less toxic to handle. Now I know that would reduce hypochlorite as well, and I know it likely couldn't reduce perchlorate, but with chlorate somewhere in the middle in terms of oxidizing potential do you think it would also be destroyed by this process?
@@integral_chemistry I honestly have no idea, I’ve never used chromium compounds in my electrolysis cells because I’ve got a toddler running around and I don’t want any trace contamination in the house that he might come in contact with. It’s the same reason I haven’t made PbO2 electrodes yet until I can get a shed or something for a proper lab space. The way the passive ph control works is the hydroxide is deposited on the cathode in basically the same way it would be with chromium hydroxide but it’s considerably thicker and quite visible, the chloride or sulfate ions then help balance the ph. At least that’s how I interpreted it, I first came across it in videos by the mysteriusbhoice channel. If I were dealing with a cell liquor with dichromate in it I’d probably just recycle it into the next run, but you should be able to crystallize your chlorate out (you’d use something like persulfate if you were making perchlorates with a lead dioxide electrode) then any way you can reduce the dichromate to the hydroxide or any lower oxidation state would likely precipitate out as well as being considerably less toxic. Though like I said, I’d probably just put it aside and use it as the base solution for my next run with more NaCl added.
@@integral_chemistry Dithionite redox potential at pH=7 is -0.66 V, chlorate potential at pH=6.8 is 0.81 V. By the book dithionite could reduce chlorate too, but both processes have many intermediates and are strongly dependent on pH. I'd say adding dithionite drop by drop while mixing could theoretically reduce hypochlorite first without affecting chlorate yield much but it would still leave a mixture of different chlorine/sulfur compounds.
One of the seasons I love your videos is, because you make the crystallisation so satisfying to watch.
Thank you! I'm glad you think so. What I really need is to figure out how to do time lapse, because some of the most satisfying Crystallizations take hours. Even this short one ended up being a 10GB file
Have you tried the chlorine dioxide route?
Chlorine(slight excess) and Oxygen are mixed in a tube illuminated by 450nm light.
Cold water saturated with chlorine is sprayed through the chamber and it absorbs all the ClO2 being formed.
In the water, ClO2 dissociates into ClO3- and ClO2-. The ClO2- reacts with hypochlorous acid from chlorine dissolution (HOCl) to make chloride ions and chloric acid (HClO3).
The pH is adjusted by slowly adding potassium hydroxide such that the chlorine and chlorine dioxide absorption is sustained.
The KClO3 crystals settle down in the cold water while the remaining water is recirculated.
Always fun to see that stuff being made, as it is really quite useful, and its always fun to see how many useful chemicals can be bought at the hardware store!
Probably 90% of the chemicals I use are either bought at the hardware store, Walmart or made from stuff I bought there. The other 10% were bought online.
It is crazy how the vast majority of everything I use comes from regular stores. I've gotta go to walmart today, and I have a separate shopping list for "science stuff" (methanol, isopropyl, lead/tin sinkers, sulfuric acid/hydroxide drain cleaner, etc.)
I remember recrystallizing my first bath of potassium chlorate. A beautiful flask filled with hexagonal plates, some of which were about 15 mm in length. I had then moved to external cooling for recrysts and would obtain small but purer shiny crystals. KClO3 is a solid first choice for recrystallization
I just got back into teaching and I think this is going to be my go-to recrystallization demo (it used to be potassium nitrate)
@@integral_chemistry Potassium nitrate crystals are AWESOME. I super-saturate KNO3 on the hot plate, then transfer it to a mason jar and put it under a mild vacuum to cool. The resulting crystal growth is incredible. There are few crystals as beautiful and satisfying to grow than KNO3.
i love recrystalizing chlorate because of the extremely colourful square crystals
It always shocks me how beautiful it is. Yet to find a Recrystallization I like more (urea looks cool, but the resulting crystals are a buzzkill to dry completely)
@@integral_chemistry did you film that through a polarizing filter or do the crystals have those colors with the naked eye?
Good job!
Such a pretty compound indeed 😍 it’s amazing to see how many compounds can be synthesized from hypochlorites and chlorates. I would love to see some perchlorate synthesis from you sir 🔥🙏🏼
It really is pretty! And I do plan on doing a vid on perchlorate, but my issue is that you need chlorate as a starting material. Potassium chlorate/perchlorate is kinda too insoluble for a good yield (so far) and sodium chlorate is basically impossible to separate from sodium chloride.
I'm sure I'll figure it out eventually though!
@@integral_chemistryLooking forward too it as an amateur chemist your videos are very helpful!
the timing on this video is crazy ive been looking at different synthesis methods for this or just trying to buy online without spending massive amounts of money
Wow yeah weird coincidence. Definitely recommend the pool shock method unless you already own a bunch of electrolysis equipment
Thanks!
Until 2016 when pure alkali chlorates was banned in the EU (it's still allowed to possess it only in mixtures up to 40 %), I synthesized it by a double displacement reaction between calcium hypochlorite and potassium carbonate. You only got to filter off the resulting calcium carbonate to get a pure solution of potassion hypochlorite in the filtrate which is easy to disproportionate into chloride and chlorate. The chlorate crystallizes out on letting it cool down to room temperature.
I never succeeded with electrolyses using carbon anodes because they always got completely corroded...
And with bleach I only got a heavily NaCl contaminated product or extremely low yields after recrystallization.
Interestingly pure alkaline earth chlorates and perchlorates as well as perchloric acid are still legal here... 🙄
I do think it's funny that alkaline earth chlorates and perchlorate would be legal, as anyone determined to do anything nefarious wouldn't be discouraged by the extremely easy conversion to the alkali salt..
I wish perchlorate was easier to get, and I do love your idea using the potassium carbonate (no idea why I didn't do it that way).
Your method does give me an idea though! I've been trying to work out how to get pure sodium chlorate (without chloride contamination) as a starting point for perchlorate. That said I'd think barium chloride and sodium carbonate could be a good path forward
Much like how locks only keep our honest people, EU rules only keep out those with 0 chemistry knowledge.
What's even more odd, at least in my country not even all alkali salts are covered. Only sodium and potassium salts of chlorate and perchlorate are banned by name. Lithium perchlorate for example is still freely purchasable, AFAIK.
@@TunkkisSame here in the EU. 😏
@@integral_chemistry
I guess you meant barium chlorate, didn't you?
Using barium chloride will end up in sodium chloride - makes no sense when your target product is chlorate.
@@experimental_chemistry Oh yeah I meant adding barium chloride to precipitate barium chlorate, then isolation and addition of sodium carbonate to precipitate the barium carbonate and isolate the resulting sodium chlorate
I like the sound of the gummy bears screaming as the life leaves thier bodies.
Me thinks your a very sick person ! Want to be friends! ?
A beautiful, informative, well made video. I would be very interested in you making a video where you work up table salt to crystalline SC. Unlike the potassium salt, SC is the work horse for labs, precisely because of its high solubility in water, making it more suitable as a reagent, for instance in generating halogens or oxidation reactions. In 1% solution it also is a great driveway herbicide, made from just salt water and (solar?) power. You might make use of "salting out" the SC by resaturating the hot salt solution with NaCl, then cooling, as is done in the industry. Salt + electricity --> SC makes for a sensational video concept. Put your growing chlorate cell knowledge to work in tackling an easy SC cell and win the internet! Potassium chlorate is niche, SC is the totally versatile anythng-you-want Chlorate.
But so hygroscopic...
Including the cost of electricity, how much cheaper would you say the sodium chloride electrolysis method is compared to using calcium hypochlorite?
I've tried adding a small amount of ethanol to my water/KClO solution during the purification step to lower the freezing point and alter the solubility of the solution to push more KClO out while retaining any salt (I started with bleach). I'm no chemist, way more of a technician, so am I correct about my idea? The gummy bear test works on my product of course; it doesn't have to be super pure for that.
Nice job. Can you make a video about the reaction of this perchlorate with lactose, starch and cellulose ?
still working on perchlorate, but once its finished that would be a cool idea!
@@integral_chemistry a video where you compare reaction on those saccharides
About dripping hydrochloric acid. I got an idea but I'm not sure if it will work. I'm thinking about putting a clay pot and use it as a diaphragm. The fill the clay pot with hydrochloric acid.
could i do this electrolysis just to make sodium chlorate? when will it recrystalize?
Is there a buffer solution that can be used effectively to keep the pH down without messy side reactions?
I believe I saw someone suggest magnesium chloride. Idea there is that magnesium hydroxide is insoluble and would settle out instead of allowing hydroxide concentration in solution to keep building up. I do fully intend to try it but so far I haven't gotten around to it. Calcium hydroxide could maybe work too, but its more soluble and it requires a higher pH to form in the first place.
i had a big 20L mmo and titanium cell going one summer i just did driect electrolysys of KCl to KClO3, product was periodicaly scuuped up from the bottom with thos sqare aquarium netts, and had an floating kcl addition chamber, needed little attention just checking consentration with refractometer harvesting and repleneshing the kcl floate. it had an output of around 50g a day, so had more kclo3 then i knew what to do with so used most to nuke all weeds around
LMAO that's awesome! I'm thinking of something similar for my perchlorate cell (with the Periodic recovery of product). Issue is every anode I try using for perchlorate gets absolutely destroyed.. I should probably bite the bullet and make a MMO anode
@@integral_chemistryi just orderd an mmo on titanium mesh 20x 30cm was abut 150usd or so
Seeing those iridescent crystals of potassium chlorate crystals coming out of solution and 'snowing' made me think: how about a Snow Globe based on potassium chlorate?
Potassium chlorate decomposition:
4KClO3 -> 2K2O + 2Cl2 + 5O2
This is why it is such a good oxidizer, because it releases lots of oxygen.
عمل ممتاز استمر في عملك احب ما تفعلة شكرا لك على الفيديو.
Awesome! Can tungsten be used as cathode too
Honestly you can use most anything for the cathode, it's really the anode that needs to be made of something more chemically durable
@@integral_chemistry thank you
Stupid question…
You went to all the trouble of electrolysis of a NaCl solution and then converted to potassium.
Couldn’t you just run a KCl solution through electrolysis and save some time/steps? Am I missing something?
Good question actually! The issue is that the potassium chlorate is so insoluble I worried it would precipitate on the electrodes or crystallize out and reduce efficiency
@@integral_chemistry
If there is enough room in the bottom of the electrolysis cell ( under the electrodes ), wouldn’t any precipitate that forms on the electrodes, fall off and collect on the bottom of the electrolysis cell?
It was sort of hard to believe those colorful rhombuses during crystallization are even real. I see what you mean now.
How do you make Ammonium chlorate without Sodium chlorate in the first place?
"My cathode is bigger than your cathode" 😅
LMAO it is obnoxious. Tbh it was smaller relative to the beaker and carbon rods in my mind's eye (I have terrible visual memory 😅)
@@integral_chemistry I'm just being sarcastic (Bostonian default)... was a perfect opportunity 🤣
TIL how gatorade was made
But did you use reagent-grade gummy bears?
lol uhhhh haribo?
@@integral_chemistry You should send CoA request to Haribo...
Potassium permanganate for a side , how favorable, looks like it might make a half crystal
have you tried the potassium carbonate and chlorine method
I've tried that method. It works, even with the 'bonfire ash grade' potassium carbonate I used. Carbon dioxide bubbles out of solution as the chlorine reacts with the carbonate, forming potassium hypochlorite. You then heat the potassium hypochlorite solution to 70 degrees C for a few hours to encourage disproportionation to chlorate and chloride. Still, the electrolytic route is more efficient.
it really is the most beautiful crystal @@garycard1456
Pro tip: the cathode should be smaller
yeaaah it was a bit huge, definitely not the most efficient setup possible
1. Never play with kclo3, its unstabile. only kclo4 is safe. Titanium cathode, pbo2 anode, 5 volt 30 amp, run for 7 days, test with methylen blue. This is the right and safe way. This video has so many fails.
Perchlorates are also unstable, I wouldn't recommend "playing" with any oxidizer. You can use basically anything for a cathode as it won't degrade, and while yes lead dioxide is the holy grail of anodes, they are extremely difficult to buy and very dangerous to make. Current and voltage actually don't matter much, current DENSITY is the most important factor which is dependent on the surface area of the anode. The time you need to run it is also dependent on volume and concentration of electrolyte, and methylene blue is more useful for checking the transition of chlorate to perchlorate. Sounds like you're just regurgitating a specific procedure from another video you saw.
Like this comment