Sciencemadness Discussion Board

KClO3 from lie,too easy! (?)

mfilip62 - 31-3-2010 at 08:26

Hy,

I was searching this forum few times and was stunned that
nobody posted this method,but instead you screw up with
complicated and expensive electrolysis.
If it was posted,just delete this topic.

All you need is very inexpensive and readily available,
bit of creativity and sanity;

Dissolve 5g of KNO3 in cca. 15ml of water
in some kind of tall glass(inert) pipe with lot of inert glass balls inside
for max efficiency.(you can use Erlenmeyer flask instead or simple
bottle,it also works great)
Heat it gently at about 60°C (It works without heating for me...)
and bubble chlorine gas trough it.

(I will add picture to visualize apparatus when crappy Internet of mine
lats me.)

(there are few easy and inexpensive methods to produce it,depending on what you have; like HCl+NaClO (bleach) and HCl+KMnO4

seal a reaction flask with a wet cotton ball stained with ink.
When ink color disappears reaction is probably done.

Cool down solution in ice bath,your KClO3 will be recrystallize,
filtrate it and let it dry,you can wash it with acetone or some non-polar solvent to speed things up and get rid of chlorine,but i am not sure if this is good idea since it is oxidizer and solvents are fuels...
when it stops smelling like chlorine its safe to use in most pyro compounds.

Hope his helps!

For rookies;
KOH is extremely dangerous substance if comes in contact with eyes or skin,chlorine is noxious war gas,so do it outside only!


For experienced members;
Product looks crystal clear and I got more than 70% efficiency in my firs synth! Works fine with gummy bear :D
What do you guys think about this method!?

Hamilton - 31-3-2010 at 08:49

What about the KNO3? you don't even use "lie" and it should be written lye. KNO3 wont transform to KClO3...

If you substitute KNO3 with KOH it may work a little

I think this is not good for anything.

[Edited on 31-3-2010 by Hamilton]

1281371269 - 31-3-2010 at 09:01

Gah no need to prey on what are easily dismissed as innocent mistakes.

It could be a good method, especially if you have no gifts with electricity and want an easy method of making a few grams of high purity KClO3 for uses other than pyro (if it has other uses?)

But it also sounds like it would be very inefficient for larger quantities, not necessarily in terms of yield but in terms of the time it takes.

hissingnoise - 31-3-2010 at 09:58

Quote:
I was searching this forum few times and was stunned that
nobody posted this method,but instead you screw up with
complicated and expensive electrolysis.

It's hard to take your post seriously!
Quote:
All you need is very inexpensive and readily available,
bit of creativity and sanity;

Your newfound method is the one Berthollet used (and found seriously wanting!) in the 1780s.
Chlorates only became generally available with the development of electrolytic methods. . .
Too easy indeed?



DJF90 - 31-3-2010 at 09:59

Quote:
an easy method of making a few grams of high purity KClO3 for uses other than pyro


For a start, it doesn't sound like it will work, but I'm not one to dismiss a procedure I haven't heard of. Secondly, no-one said anything about "high purity", and if this did work, I hightly doubt it would be more pure than conventional (electrolysis) methods.

Uses of KClO3 that aren't pyro orientated are a) heating to make KClO4 and KCl, b) reaction with PCl3 to give POCl3, and c) reaction with acid to form ClO2, which could be useful for one thing or another (it can be used to make sodium chlorite (NaClO2)?)... of course there are likely a few other uses but these are the ones that spring to mind.

EDIT: Hissingnoise got there before me... It appears the procedure does work, although by the sounds of it, poorly. The rest of what I said still stands

[Edited on 31-3-2010 by DJF90]

bbartlog - 31-3-2010 at 10:05

Quote:
instead you screw up with
complicated and expensive electrolysis.
(...)
and bubble chlorine gas trough it.


Different people may have different ideas about what is easy or practical, but I personally rate 'methods that involve gaseous chlorine' as less home chemist friendly than mere electrolysis. Granted that there are a lot of wrinkles to KClO3 via electrolysis, including difficulties with finding suitable electrodes, but it's not particularly intractable and can be quite efficient if you want a lot of chlorate. I do like the proposed method for small quantities, though.

blogfast25 - 31-3-2010 at 10:08

I'd never heard of Berthollet's route to KClO3 but here it is:

http://www.backyardchem.com/chlorates.php

No KNO3 in sight...


DJF90 - 31-3-2010 at 10:26

I made KClO3 like that when I was at school... Yeild isn't good but purifaction isn't too bad (KClO3 has a nice solubility curve) and upon crystallising and recystallising, iodometric titration gave a purity of about 90% IIRC (maybe higher). No doubt it would be easy to improve on this (recrystallisation wasn't my favourite thing to do at the time so I may have fudged it a bit).

EDIT: Actually... scrap that... we made KIO3 not KClO3!

[Edited on 31-3-2010 by DJF90]

[Edited on 31-3-2010 by DJF90]

Xenoid - 31-3-2010 at 11:08

Quote: Originally posted by mfilip62  

but instead you screw up with
complicated and expensive electrolysis.


WTF... What are you on about! Very few chemical processes are cheaper, simpler and more elegant and effective for the home experimenter than the electrolytic formation of chlorates. One can spend as little (~$0.00) or as much ($100's) building a cell.

Hey, you could make the Cl2 and KOH by electrolysis ... what a good idea ... not!

Quote:
I got more than 70% efficiency in my firs synth!


Well, you have done better than industry... as quoted in Mellor:

"Potassium chlorate can be prepared in the laboratory this way, but industrially the method is wasteful since five-sixths or the potassium hydroxide used is converted to potassium chloride..."

6KOH +3Cl2 --> KClO3 + 5KCl + 3H2O

This method also makes... water!

The electrolytic method was developed precisely because of these shortcomings!


UnintentionalChaos - 31-3-2010 at 12:00

Quote: Originally posted by Xenoid  

Quote:
I got more than 70% efficiency in my firs synth!


Well, you have done better than industry... as quoted in Mellor:

"Potassium chlorate can be prepared in the laboratory this way, but industrially the method is wasteful since five-sixths or the potassium hydroxide used is converted to potassium chloride..."

6KOH +3Cl2 --> KClO3 + 5KCl + 3H2O

This method also makes... water!

The electrolytic method was developed precisely because of these shortcomings!



I'd say that in light of that properly balanced equation, 70% conversion is spooky magic.

1281371269 - 31-3-2010 at 15:45

I'd say in light of that equation, mfilip62 could still claim he was correct by saying that by 'efficiency' he meant yield. He might have had 98% yields, It's the atom economy that's poor.

mfilip62 - 1-4-2010 at 10:03

Of course it is KOH, I wrote KNO3 as mistake in hurry and now can't edit. (!?)Isn't it obvious?!
Jesus,why are you being such linguistic Nazis!
And yes,Mossydie is right,it is yield!

Well,I used 5g of KOH and got around 6,5g of KClO3,
it is recrystallized and VERY pure.
Made some flash powder today and it is as good as with
commercial high-grade stuff.

Most of you people live in the box,or too much democracy makes
your brainwashed!?

Its almost impossible to obtain ANY chemical here,
unlike Netherlands,USA...not mentioning right electrodes!
All you do is improvisation,trial and error...

I just tried to help people who want pure KClO3 in small quantities.

We have 19th century retarded chemofobic law on poisons,
so any chemical I have I must make or smuggle in.

woelen - 1-4-2010 at 10:27

You must be a magician. From 5 grams of 100% pure KOH and with no limits on chlorine supply you cannot obtain more than 1.82 grams of KClO3, unless you have some magical touch in making interesting chemicals :D

I am not a magician and I simply have to obey the yield according to the following equation:

6KOH + 3Cl2 --> KClO3 + 5KCl + 3H2O

UnintentionalChaos - 1-4-2010 at 15:57

Quote: Originally posted by mfilip62  
Of course it is KOH, I wrote KNO3 as mistake in hurry and now can't edit. (!?)Isn't it obvious?!
Jesus,why are you being such linguistic Nazis!
And yes,Mossydie is right,it is yield!

Well,I used 5g of KOH and got around 6,5g of KClO3,
it is recrystallized and VERY pure.
Made some flash powder today and it is as good as with
commercial high-grade stuff.

Most of you people live in the box,or too much democracy makes
your brainwashed!?

Its almost impossible to obtain ANY chemical here,
unlike Netherlands,USA...not mentioning right electrodes!
All you do is improvisation,trial and error...

I just tried to help people who want pure KClO3 in small quantities.

We have 19th century retarded chemofobic law on poisons,
so any chemical I have I must make or smuggle in.


It says you've been here since 2006, so why do you come across as a k3wl/troll? Most people who've been here that long have learned not to be idiots.

Skyjumper - 1-4-2010 at 17:25

Could be the 61 posts in a little under 4 years. Just sayin' and "expensive electrodes" I don't use platinum electrodes. (I do have some thin thin platinum wire though...)

Jimmymajesty - 7-4-2010 at 06:32

I only needed a small amount of KClO3 to make some flash powder and stuff:) I am very familiar with the theory of making chlorates by electrolysis, but I never got the balls to use dichromates in my lab. Actually I would never use something accumulative as it will end up in your brain, kidney etc.. or oxidise you DNA like chromates. No matter how good your fume hood or gas mask or glowe is or whatever you got.. you will eventually get into contact with the material unless you do it far away from your home and only the final product will be taken to home. You will certainly sorry for handling such a harmful chemical in long term!

In my work we empoly chromate containing catalysts for polymerisation purposes. The ANTSZ (the agency that check the use of hazardous chems) is coming every year and collect dust from apparatus, glove box, etc. and analyse that, furthermore we have to go to blood test in every year, and carcino embrional RNS screening.

Also a college of my mother worked with chromates, she measuerd 2g of dichromate in every other week, and her blood's chromate content was unacceptable high as it turned out at the screening.

Sorry for my chemofobia:) but these are facts!

So I stick with the good old KOH+Cl2 method, The KOH is valuable so I replaced a part of the KOH to NaOH. The foaming is quite extreme at some point, so you dont want to fill the flask more than 1/3rd. You will notiche the end of the reaction by the color change, furthermore adding chlorine after the completion, foaming ceases and can not be observed for further chlorine administration. It is also important to keep the glass inlet tube above the solution or the KClO3 solidifies into it. The KClO3 crystallizes on cooling.

Jor - 7-4-2010 at 07:04

Ofcourse chromate is carcinogenic and you should avoid exposure. But a little exposure is no more harmful that breathing smoke from a wood fire or a sigaret being smoked next to you.

Remember that the previous generation was exposed to lots of carcinogenic chemicals (paints, pesticides, household cleaners, etc) wich are now banned, and most of them still get 75-80 years old.

In my opinion it's a good thing to ban these carcinogens in common products and avoid the chemical if there is a safer alternative. With this way of living we already get a lot less exposure than our parents and grandparents, and have an increasing chance to get older. But people nowadays overreact completely, and I think you overreact as well in this case. They can't accept they get 90% (or even 99%) less exposure, no they want ZERO exposure, wich leads to this paranoia of every carcinogen even being banned in labs. I find it scary when scientists cancel an experiment because they are too afraid to use a gram of dichromate in solution. Just work with caution!

Nicodem - 7-4-2010 at 07:56

Quote: Originally posted by mfilip62  
Of course it is KOH, I wrote KNO3 as mistake in hurry and now can't edit. (!?)Isn't it obvious?!
Jesus,why are you being such linguistic Nazis!

It simply can not be obvious that you meant KOH when you write KNO3. I also thought you indeed meant KNO3 because you present your method as something new. If it was KOH, then what is there new and where are any references? The only thing that made me suspect of it being a typo was in that KNO3 does not react with Cl2 and that warning about KOH at the end.
And by the way... Accusing others of being "linguistic Nazis", while you present a Nazi quisling state as your location in the member's profile, is tasteless.
Quote:
And yes,Mossydie is right,it is yield!

Well,I used 5g of KOH and got around 6,5g of KClO3,
it is recrystallized and VERY pure.

6.5g KClO3 from 5g KOH would be a 357% yield which is obviously nonsense! The theoretical yield from that amount of KOH is 1.82g KClO3. And you claim it as pure? Perhaps you made another typo?

hissingnoise - 7-4-2010 at 07:58

Dichromates aren't actually needed for NaCl electrolysis!
It's not like you're producing chlorates on the industrial scale where efficiency and the bottom line are paramount.
A NaCl solution with dilute HCl for addition to make up for evaporation and alkaline drift is all that's required. . .

Nicodem, was casting up Croatia's distant past really neccessary?




[Edited on 7-4-2010 by hissingnoise]