Trifluoroacetic
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Triple Salt Frees halogens with ease!
Today I discovered on accident that triple salt/oxone will oxidise the halogens in halide salts to there elemental form. I was playing around with a
few drops of Cuprous Iodide solution and decided to add some Oxone to it and to my amazement small specs of I2 floated to the top of the solution.
Oxone solution should be useful for preparing bromine and chlorine too.
Just an FYI I dumped the iodine down the drain. I have no use for it but Br2 I would certainly love to have in bulk!
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AndersHoveland
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You are aware that there are several other ways of oxidizing halides to their respective halogen elements, which do not
require persulfate ?
Acidified H2O2 works on iodides and bromides. Indeed, even the odor of chlorine is detectible when H2O2 and NaCl react if the solution is acidic
enough (30% conc acid), although production of chlorine by this method is not very feasible.
For producing Cl2, simply add acid to bleach.
Formation of Chlorine from H2O2 and HCl
"The catalytic decomposition of hydrogen peroxide in either hydrogen chloride solution or with chlorine has been shown to be closely related to
the two chemical reactions
H2O2 + (2)H(+) + (2)Cl(-) ---> Cl2 + (2)H2O
H2O2 + Cl2 ---> O2 + (2)H(+) + (2)Cl(-)
and is believed to be due to the occurence of these two competing reactions at equal rates."
Livingston and Bray, J. American Chem. Society, Volume 47, p2069 (1925)
In this reaction no net generation of chlorine results from the action of dilute solutions of hydrogen peroxide on hydrogen chloride, but there does
exist an elemental chlorine intermediate in the reaction, which could potentially chlorinate enols.
When 30% concentrated HCl and 30% H2O2 is used then there develops a slight greenish yellow color and a faint but distinctive odor of chlorine, yet
the gas from the bubbles is still mostly O2. I conducted this expiriment and observed only moderate steady bubbling that persisted for several hours.
It is mentioned in the literature that chlorine gas is evolved from 30% solutions of HCl and H2O2, although in more dilute solutions, only oxygen is
generated.
"Oxidation of Hydrogen chloride with hydrogen peroxide in aqueous solution" V.I. Skudaev, A.B. Solomonov
To explain the catalytic action of the HCl in the reaction, I suspect that H2O2 intially oxidizes HCl to HOCl, then the HOCl reacts with more H2O2.
Even if the HOCl was oxidized to chlorous acid (HClO2), this also would be effectively reduced by H2O2, liberating oxygen.
[Edited on 18-5-2011 by AndersHoveland]
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Trifluoroacetic
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Yes I am it just seems like an easy way to oxidize halides to their elemental forms without needing to you strong acids, multiple chemicals, etc.
I've used bleach and HCL to generate Br2 in the past. I've also used H2SO4 for iodine and bromine but this stuff is quite easy to use.
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