thebean
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Oxidizing Chlorides
I was wondering if there is a way I could oxidize potassium chloride to the hypochlorite, chlorate or perchlorate? I was thinking put the kcl in a
closed vessel or in a solution and bubble oxygen into it, maybe I'd need a catalyst of some kind?
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bismuthate
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UTFSE.
Chlorates can be made via electrolysis.
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thebean
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I should mention I wanted to do this without any form of electrochemistry. I'm so sorry that the fucking search engine can't always be as accurate as
just outright asking
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bbartlog
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Bubbling oxygen into KCl won't do the job. Would be nice if it were that simple.
Bubbling Cl<sub>2</sub> into a hot solution of KOH would, if chlorine is something you have access to.
Or you can simmer bleach for a while to disproportionate it into NaCl and NaClO<sub>3</sub>, and then add KCl to precipitate
KClO<sub>3</sub> on cooling.
The less you bet, the more you lose when you win.
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bismuthate
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Sorry about that.
I don't belive that introducing oxygen to it will work. You best bet is a strong oxidiser, but that wouln't work most likely.
P.S. I've always wondered how Mn2O7 would react with halides.
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MrHomeScientist
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Quote: Originally posted by thebean  | | I should mention I wanted to do this without any form of electrochemistry. I'm so sorry that the fucking search engine can't always be as accurate as
just outright asking |
Try not to take too much offense - around here, UTFSE is usually taken to mean Use The Forum Search Engine. Though I admit I always
read it the other way for giggles.
We also tend to discourage "outright asking" with no signs of research on your part. Make some effort, and you're much more likely to get good
answers.
Electrolysis is probably the best way to go, but if you're set against it you can use the bleach method as mentioned above. There's plenty of videos
of that on YouTube, including on my channel: http://www.youtube.com/watch?v=7MsHq_dUfnY
Doesn't get much simpler than bleach and sodium-free salt, but the yields are quite low.
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bfesser
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| Quote: Originally posted by thebean | | I should mention I wanted to do this without any form of electrochemistry. I'm so sorry that the fucking search engine can't always be as accurate as
just outright asking |
But that shouldn't be a barrier to you at least putting in a little effort in searching
and answering your own questions. Show us what you've found so far.
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thebean
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| Quote: Originally posted by bfesser | | Quote: Originally posted by thebean | | I should mention I wanted to do this without any form of electrochemistry. I'm so sorry that the fucking search engine can't always be as accurate as
just outright asking |
But that shouldn't be a barrier to you at least putting in a little effort in searching
and answering your own questions. Show us what you've found so far. |
I've done research on the topic of KClO3 electrolysis, and from what I've gathered, you heat a solution of KCl and run an electrical current through
it, voltage and amperage I don't know. I've done the disproportionation of NaClO to NaClO3 and then adding KCl to it and the yield was mediocre and
impure. I didn't think that my idea of bubbling oxygen was logical, but a man can dream. I've heard of bubbling Cl (I can set up a chlorine generator
pretty easily) into KOH, but I don't have a lot of KOH and what little I have is precious. I could just use my NaOH to make NaClO3 and then do a
displacement reaction with KCl, similarly to the last step of the NaClO-->NaClO3 + KCl --> KClO3.
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thebean
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| Quote: Originally posted by MrHomeScientist | | Quote: Originally posted by thebean | | I should mention I wanted to do this without any form of electrochemistry. I'm so sorry that the fucking search engine can't always be as accurate as
just outright asking |
Try not to take too much offense - around here, UTFSE is usually taken to mean Use The Forum Search Engine. Though I admit I always
read it the other way for giggles.
We also tend to discourage "outright asking" with no signs of research on your part. Make some effort, and you're much more likely to get good
answers.
Electrolysis is probably the best way to go, but if you're set against it you can use the bleach method as mentioned above. There's plenty of videos
of that on YouTube, including on my channel: http://www.youtube.com/watch?v=7MsHq_dUfnY
Doesn't get much simpler than bleach and sodium-free salt, but the yields are quite low. |
Sorry that I'm so pissy sometimes  . I should have including the information I've
gathered and you're right on that, thank you for being patient with me, I've been a little angry with life lately. On an unrelated note, I'm quite
ecstatic that you replied to my post. I love your videos!
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AJKOER
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Treating a highly ionic suspension of Mg(OH)2 (from NaOH and MgSO4, as one preparation path, but do NOT use aqueous NH3 as the base as any residual
NH4SO4 contamination could form the highly unstable/explosive NCl3 upon chlorination) with Cl2. The Mg(ClO)2 formed is highly unstable
disproportionating readily into Mg(ClO3)2 and MgCl2 with very little heat or even treatment with air/O2 (so the answer is yes to your question if you
select the right hypochlorite!). Source: see "The Manufacture of Sulphuric Acid and Alkali: Ammonia-soda, various ..." by Georg Lunge, an online
googlebook, link: http://books.google.com/books?id=FnrTAAAAMAAJ&pg=PA669&a... . To quote from page 669:
"Now chlorine was passed into a milk of- magnesium hydroxide and water, at temperatures between o° and 100°. Even at 0°, together with magnesium
hypochlorite, much chlorate was formed, more than corresponding to half of the chlorine entering into the reaction. At 15° a little more chlorate was
formed, together with much hypochlorate, some of which was changed into chloride, with evolution of oxygen. In both solutions the hypochlorite is
easily converted into chlorate, not merely by heating to 50°, but even by prolonged agitation by a current of air at ordinary temperatures. At 70°
C, from the first mostly chlorate was formed, with a little chloride, produced by loss of oxygen. Hence magnesium hypochlorite in statu noscendi does
not possess much stability and is easily transformed into chlorate."
To form KClO3, add KOH and filter out the Mg(OH)2, or more traditionally, add KCl to the aqueous Mg(ClO3)2 and cool to separate out the Potassium
chlorate.
--------------------------------------------------------------------
For the more advanced path, add a touch of Acetic acid/acetate, NaCl and even sunlight to the brew. Some sources:
to quote a 2000 paper (link: http://pubs.acs.org/doi/abs/10.1021/ic991486r ):
"Acetic acid has a second catalytic role through the formation of acetyl hypochlorite, which is much more reactive than HOCl in the transfer of Cl+ to
ClO2- to form ClOClO."
Another article, "Effect of Chloride Ion on the Kinetics and Mechanism of the Reaction between Chlorite Ion and Hypochlorous Acid" link:
http://www.researchgate.net/publication/23141635_Effect_of_c... , to quote:
"Moreover, they found that acetate ion accelerates the formation of ·ClO2 enormously." and also "It was interpreted by a steady-state formation and
further reactions of acetyl hypochlorite. "
With respect to the role of chlorides in promoting chlorate formation, the authors states in the abstract, to quote:
"It is found that the presence of the chloride ion significantly increases the initial rate of ·ClO2 formation."
Cited reactions involving active chlorine species to accelerate the formation of a chlorate include:
Cl2O2+ H2O --> ClO3- + Cl- + 2 H+ (page 2 eq 5)
Cl2O2 + HOCl --> ClO3- + Cl2 + H+ (page 2 eq 8)
where Acetyl hypochlorite is expected in having a catalytic role.
Photolysis most likely proceeds along the following paths involving the species ·Cl, ·OH and ·ClO:
Cl2 + hv --> 2 ·Cl
2 ·Cl + 2 HOCl --> 2 ·OH + 2 Cl2 (g)
2 ·OH + 2 HOCl --> 2 H2O + 2 ·ClO (forming some Cl2O2)
Cl2O2 + HOCl --> HClO3 + Cl2(g)
where the presence of sunlight, free Chlorine and Hypochlorous acid are required in this particular chain.
Source: See for example "Photolysis of free chlorine species (HOCl and OCl- ) with 254 nm ultraviolet light" page 281 attached, and also Table 2, page
797 at http://www.geosci-model-dev-discuss.net/3/769/2010/gmdd-3-76... .
Attachment: 278FengSmithBolton2007.pdf (171kB)
This file has been downloaded 461 times
[Edited on 29-10-2013 by AJKOER]
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thebean
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| Quote: Originally posted by AJKOER | Treating a highly ionic suspension of Mg(OH)2 (from NaOH and MgSO4, as one preparation path, but do NOT use aqueous NH3 as the base as any residual
NH4SO4 contamination could form the highly unstable/explosive NCl3 upon chlorination) with Cl2. The Mg(ClO)2 formed is highly unstable
disproportionating readily into Mg(ClO3)2 and MgCl2 with very little heat or even treatment with air/O2 (so the answer is yes to your question if you
select the right hypochlorite!). Source: see "The Manufacture of Sulphuric Acid and Alkali: Ammonia-soda, various ..." by Georg Lunge, an online
googlebook, link: http://books.google.com/books?id=FnrTAAAAMAAJ&pg=PA669&a... . To quote from page 669:
"Now chlorine was passed into a milk of- magnesium hydroxide and water, at temperatures between o° and 100°. Even at 0°, together with magnesium
hypochlorite, much chlorate was formed, more than corresponding to half of the chlorine entering into the reaction. At 15° a little more chlorate was
formed, together with much hypochlorate, some of which was changed into chloride, with evolution of oxygen. In both solutions the hypochlorite is
easily converted into chlorate, not merely by heating to 50°, but even by prolonged agitation by a current of air at ordinary temperatures. At 70°
C, from the first mostly chlorate was formed, with a little chloride, produced by loss of oxygen. Hence magnesium hypochlorite in statu noscendi does
not possess much stability and is easily transformed into chlorate."
To form KClO3, add KOH and filter out the Mg(OH)2, or more traditionally, add KCl to the aqueous Mg(ClO3)2 and cool to separate out the Potassium
chlorate.
--------------------------------------------------------------------
For the more advanced path, add a touch of Acetic acid/acetate, NaCl and even sunlight to the brew. Some sources:
to quote a 2000 paper (link: http://pubs.acs.org/doi/abs/10.1021/ic991486r ):
"Acetic acid has a second catalytic role through the formation of acetyl hypochlorite, which is much more reactive than HOCl in the transfer of Cl+ to
ClO2- to form ClOClO."
Another article, "Effect of Chloride Ion on the Kinetics and Mechanism of the Reaction between Chlorite Ion and Hypochlorous Acid" link:
http://www.researchgate.net/publication/23141635_Effect_of_c... , to quote:
"Moreover, they found that acetate ion accelerates the formation of ·ClO2 enormously." and also "It was interpreted by a steady-state formation and
further reactions of acetyl hypochlorite. "
With respect to the role of chlorides in promoting chlorate formation, the authors states in the abstract, to quote:
"It is found that the presence of the chloride ion significantly increases the initial rate of ·ClO2 formation."
Cited reactions involving active chlorine species to accelerate the formation of a chlorate include:
Cl2O2+ H2O --> ClO3- + Cl- + 2 H+ (page 2 eq 5)
Cl2O2 + HOCl --> ClO3- + Cl2 + H+ (page 2 eq 8)
where Acetyl hypochlorite is expected in having a catalytic role.
Photolysis most likely proceeds along the following paths involving the species ·Cl, ·OH and ·ClO:
Cl2 + hv --> 2 ·Cl
2 ·Cl + 2 HOCl --> 2 ·OH + 2 Cl2 (g)
2 ·OH + 2 HOCl --> 2 H2O + 2 ·ClO (forming some Cl2O2)
Cl2O2 + HOCl --> HClO3 + Cl2(g)
where the presence of sunlight, free Chlorine and Hypochlorous acid are required in this particular chain.
Source: See for example "Photolysis of free chlorine species (HOCl and OCl- ) with 254 nm ultraviolet light" page 281 attached, and also Table 2, page
797 at http://www.geosci-model-dev-discuss.net/3/769/2010/gmdd-3-76... .
[Edited on 29-10-2013 by AJKOER] |
The first suggested synthesis seems a little unnecessary.
"You need a little bit of insanity to do great things."
-Henry Rollins
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Finnnicus
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The Mg(ClO2)2 based method is suggested because Mg(ClO2)2 disproportionates at and just above RT.
Useful if you don't want to boil bleach.
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thebean
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| Quote: Originally posted by Finnnicus | The Mg(ClO2)2 based method is suggested because Mg(ClO2)2 disproportionates at and just above RT.
Useful if you don't want to boil bleach. |
I need to read more carefully  I might try this approach someday.
"You need a little bit of insanity to do great things."
-Henry Rollins
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AJKOER
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I will make the point that the amount of water present is particularly important. Per US Patent 2,047,549, "Production of magnesium chlorate", link:
http://www.google.com/patents/US2047549 , to quote:
"The reaction proceeds efficiently provided the magnesium hydrate supplied to the chlorination is associated, as subjected to the chlorination, with
water in proportion such that the molecular ratio MgO: H2O lies between about 1:1 and 1:1.5. In this range of hydration the magnesium hydroxide
appears to be peculiarly active, particularly when the molecular ratio MgO to H2O approximates 1:1.5. "
Now, my take on how the reaction actually proceeds is as follows:
First:
Cl2 + H2O = HCl + HOCl
And then:
2 Mg(OH)2 + 2 [HCl + HOCl] --> MgCl2 + Mg(ClO)2 + 4 H2O
2 Mg(OH)2 + Mg(ClO)2 + 2 [HCl + HOCl ] --> 2 MgCl2 + Mg(ClO2)2 + 4 H2O
2 Mg(OH)2 + Mg(ClO2)2 + 2 [HCl + HOCl ] --> 2 MgCl2 + Mg(ClO3)2 + 4
H2O
Net:
6 Mg(OH)2 + 6 [HCl + HOCl] --> 5 MgCl2 + Mg(ClO3)2 + 12 H2O
Substituting Cl2 + H2O = HCl + HOCl and cancelling out some of the water, the net reaction could be rewritten as:
6 Mg(OH)2 + 6 Cl2 --> 5 MgCl2 + Mg(ClO3)2 + 6 H2O
which, of course, belies the critical important of having some water for the reaction to proceed. However, with too much water, the efficiently of the
chlorate formation apparently declines.
---------------------------------
[EDIT] From a perspective of chemistry, electrolysis forms chlorate basically (in my opinion, but not precisely for certain, as some of the chemistry
appears to be still unsettled) per the above reaction chain as well. The electrolysis of a chloride forms Cl2 and an OH-. The problems of maintaining
the pH (by removing HCl, formed by the action of chlorine and water, with stirring in the cell so as to promote HOCl creation), temperature (as to not
decompose the chlorate), and limiting water to promote the disproportionation to chlorate, all are still present. However, in my opinion, perhaps more
difficult to control in an electrolysis setting.
[Edited on 19-11-2013 by AJKOER]
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Zyklon-A
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Could one make a saturated solution of KCl, and then bubble O3 through the solution?
KCl+O3-->KClO3?
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Zyklon-A
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| Quote: Originally posted by AJKOER | I will make the point that the amount of water present is particularly important. Per US Patent 2,047,549, "Production of magnesium chlorate", link:
http://www.google.com/patents/US2047549 , to quote:
"The reaction proceeds efficiently provided the magnesium hydrate supplied to the chlorination is associated, as subjected to the chlorination, with
water in proportion such that the molecular ratio MgO: H2O lies between about 1:1 and 1:1.5. In this range of hydration the magnesium hydroxide
appears to be peculiarly active, particularly when the molecular ratio MgO to H2O approximates 1:1.5. "
Now, my take on how the reaction actually proceeds is as follows:
First:
Cl2 + H2O = HCl + HOCl
And then:
2 Mg(OH)2 + 2 [HCl + HOCl] --> MgCl2 + Mg(ClO)2 + 4 H2O
2 Mg(OH)2 + Mg(ClO)2 + 2 [HCl + HOCl ] --> 2 MgCl2 + Mg(ClO2)2 + 4 H2O
2 Mg(OH)2 + Mg(ClO2)2 + 2 [HCl + HOCl ] --> 2 MgCl2 + Mg(ClO3)2 + 4
H2O
Net:
6 Mg(OH)2 + 6 [HCl + HOCl] --> 5 MgCl2 + Mg(ClO3)2 + 12 H2O
Substituting Cl2 + H2O = HCl + HOCl and cancelling out some of the water, the net reaction could be rewritten as:
6 Mg(OH)2 + 6 Cl2 --> 5 MgCl2 + Mg(ClO3)2 + 6 H2O
which, of course, belies the critical important of having some water for the reaction to proceed. However, with too much water, the efficiently of the
chlorate formation apparently declines.
---------------------------------
[EDIT] From a perspective of chemistry, electrolysis forms chlorate basically (in my opinion, but not precisely for certain, as some of the chemistry
appears to be still unsettled) per the above reaction chain as well. The electrolysis of a chloride forms Cl2 and an OH-. The problems of maintaining
the pH (by removing HCl, formed by the action of chlorine and water, with stirring in the cell so as to promote HOCl creation), temperature (as to not
decompose the chlorate), and limiting water to promote the disproportionation to chlorate, all are still present. However, in my opinion, perhaps more
difficult to control in an electrolysis setting.
[Edited on 19-11-2013 by AJKOER] |
I think that is to much work to be worth, the time, and potentially expensive chemicals.
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