Ok I just want some clarification. the electrolysis of a halogen salt will generate the hydroxide of the cation, hydrogen gas, and a diatomic molecule
of the anion? Does that apply to all halogen salts? Also where do the end products end up? Does the hydroxide end up on the cathode, while the anion
gas end up on the anode correct? Just curious about a possible bromine production method.Oscilllator - 25-8-2015 at 17:35
Ok I just want some clarification. the electrolysis of a halogen salt will generate the hydroxide of the cation, hydrogen gas, and a diatomic molecule
of the anion?
It's not as simple as that. Assuming we are talking about aqueous chemistry here, there are a number of different possible products including
Hydroxide, hydrogen, chlorine, chlorate, perchlorate and hypochlorite.
What product forms is dependent on a number of things including temperature and whether or not there is a diaphragm present or even a mercury cathode.
If you want more detail on how these different products are formed, I suggest you read through the production section of the different wikipedia
articles on the various chlorine products that can be formed.
If you want information on bromine production methods there are a number of good guides floating about written by members here. I suggest you watch mrhomescientist's guide on the topic or read woelens article. Both of these guides cover an electrolytic method, but there are many other methods
available.DalisAndy - 25-8-2015 at 21:00
I was same goes for iodine? I was going to purify iodine tincture to crystalsDalisAndy - 25-8-2015 at 21:18
Also can I buy a proper cell for this? If so what would it be called. Or do I have to make one?elementcollector1 - 5-9-2015 at 18:58
I suppose the Hoffmann apparatus would be a good place to start, although buying something is rather ridiculous when it's so easy to make. Unless
you're talking about separating the electrode products, which is significantly more difficult.Sulaiman - 6-9-2015 at 04:05
according to Wikipedia, tincture of iodine
"It is usually 2–7% elemental iodine, along with potassium iodide or sodium iodide, dissolved in a mixture of ethanol and water"
Rather than electrolysis I would go for simple chemical reactions;
since elemental iodine is poorly soluble in water,
I would add an oxidising agent to the tincture of iodine
which will convert the iodide to iodine
so almost all of the iodine will precipitate out as a very fine suspension
which will eventually settle out,
decant off the liquid, wash with water, Purify by sublimation.
what to use as an oxidising agent?
hydrogen peroxide in slightly acidic conditions may be good as it does not produce any products that may be difficult to separate from the iodine.
P.S. add the hydrogen peroxide slowly as iodine catalyses the decomposition of hydrogen peroxide = heat + bubbling
