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Author: Subject: Strange Permanganate (?)
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[*] posted on 11-5-2015 at 20:48
Strange Permanganate (?)

Bought 500g Potassium Permanganate from 'Busy Bee Chemistry', an Ebay seller (Canadian). Advertized in the photo as pure looking purple - black crystals, I was a bit disappointed. Its a purple powder, with bits of black and brown (paper or pulp? splinters?) and seems like it has been 'cut' with something. I know technical grade isn't the best, but this is still a letdown. Additionally, there are two things that get to me. Although I have been doing plant extractions in the garage for a few weeks now, the solution in water smelled a bit sweet/ fruity, I don't know if that was just my imagination. As well, when I tried the classic Glycerin + Potassium Permanganate (with water for acceleration), it would only fizzle and smoke, it took three tries and a lot of Permanganate to get any real flames to appear, and even that was a bit lame. (A short, 1.5 - 2 second burst of flame.) I don't know what I was expecting from the product, maybe this is normal and I've watched too many youtube videos. Does anyone have any experience related or method for me to test the material? Gee
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[*] posted on 11-5-2015 at 21:11

Glycerine and permanganate is a bit dependent on the crystal size. In my school lab we have a jar of the stuff that just won't go. (The source of a few dud thermite ignitions before we figured out what was happening.) This jar is actually labelled analytical grade. The crystals are large and the glycerine just won't wet it well.
I am not sure of the best test to do to ascertain the purity. But I would not assume the worst.
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[*] posted on 11-5-2015 at 21:15

Ditto with the crystal size. If you grind it up in a mortar and pestle before mixing in the glycerol, it works much better (or so I have heard).

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[*] posted on 12-5-2015 at 00:08

Look up a recipe for 0.01 M KMnO4, prepare a small amount and check it for insoluble matter (MnO2, usually).

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[*] posted on 12-5-2015 at 00:11

Quote: Originally posted by Hawkguy  
Advertized in the photo as pure looking purple - black crystals, I was a bit disappointed. Its a purple powder [...]
Emphasis mine.
I'd say try recrystalizing it in case. Since it has some potassium permanganate, make a hot saturated solution, filter the other shit and cool and grow in an ice bath, at least twice should be alright.

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[*] posted on 12-5-2015 at 14:41

In Australia you can get high purity KMno4 from any chemist as an antiseptic, crystal size is small and comes in 50g containers. I use it to give sparklers that extra kick. Oh and to oxidize/indicate aconitic acid

Atropine, Bicarb, Calcium.
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[*] posted on 12-5-2015 at 15:00

Red-ox titration will tell you if it's cut or not, you can use oxalic acid for that.
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[*] posted on 14-5-2015 at 05:48

I get my potassium permanganate from those keep fresh packages to keep veggies in the fridge longer. They are expensive to buy, but if you look in the new fridge department at any large freezer store they have them as free samples. I just grab them all and call it a day lol. They are food grade potassium permanganate so the quality is very high. I have noticed though the colour is dark purple, a little lighter than the black powder I see on you tube, but it has always worked great for me.

Also, the potassium permanganate glyserin reaction is very dependant on ambient temperature. In the summer it reacts violently, but any temp under 15 or so degrees celcius the reaction is slower. In winter it will sometimes not react at all. I know this because some camping types use it as a fire starter and were very disappointed when cool out the reaction was not impressive.

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