Sciencemadness Discussion Board

Synthesis of Sodium Chlorate from Bleach

Maxius - 15-3-2015 at 15:11

I have a question- Can I just use an old pot I was willing to discard as the vessel to boil the bleach? I have no access to glassware unfortunately.

Etaoin Shrdlu - 15-3-2015 at 15:45

Sure, why not? I don't see why you would have to discard the pot, either, just clean it out well and use it for other experiments. Probably no harm in cooking with it, but it's best practice not to.

Reuburg - 15-3-2015 at 15:56

It should work fine. However, depending on the material of the pot which in most cases is stainless steel, it will produce amounts of Cl gas and NaOH

phlogiston - 16-3-2015 at 07:22

What is the pot made of?

Bert - 16-3-2015 at 07:53

An enameled steel pot works. Metals can react, I would avoid.

Maxius - 16-3-2015 at 08:14

stainless steel

Etaoin Shrdlu - 16-3-2015 at 10:04

The nickel will catalyze the wrong decomposition pathway, then, don't bother. (You know, I don't think I've seen a stainless steel pot in ten years. All hail Teflon.)

Maxius - 16-3-2015 at 12:00

Will Chlorox Concentrated Bleach No Scent be a good source for the sodium chlorate ? I couldnt find an MSDS for it ..

I suppose an no name brand bleach with scent will not work yes?

[Edited on 16-3-2015 by Maxius]

gdflp - 16-3-2015 at 12:52

Any bleach will "work", it will just vary the contamination of the final product. No name unscented bleach is typically best, as it is the cheapest and will contain very few additives. No Scent Clorox Bleach should work fine, the amount of contamination should be minimal. Just remember that bleach doesn't contain sodium chlorate, it contains sodium hypochlorite which needs to be boiled to decompose the hypochlorite into chlorate and chloride.

Amos - 16-3-2015 at 13:36

It will be difficult to obtain usable sodium chlorate from bleach this way. The bleach already has a significant amount of sodium hydroxide and the disproporionation reaction also produces quite a lot of sodium chloride as well. However, the sodium chlorate produced during the reaction can be used to make potassium chlorate instead if concentrated potassium chloride solution is added to the boiled-down bleach. This will cause potassium chlorate, which has a much lower solubility, to crystallize and fall out of solution.

Molecular Manipulations - 16-3-2015 at 15:15

Not necessarily. It's quite easy to make sodium chlorate from bleach.
Also typical bleach has very little sodium hydroxide, usually around 0.5% w/w.
The reaction, with heat, disproportionates like this: 3NaOCl → NaO3Cl + 2NaCl.
Since sodium chloride's solubility changes very little with temperature, you can boil it until sodium chlorate is saturated or is almost saturated at 100°C. Filter off the sodium chloride and cool the solution to get chlorate crystals.
I've done this several times and it works fine. The best thing to do is calculate how much chloride will be present rather than eyeball it or worse yet - guess.
Yeah it's super easy to get potassium chlorate, but you can make that from sodium chlorate, and not vice-versa.

AJKOER - 19-3-2015 at 13:07

May I suggested you also investigate a simplied photolysis analysis approach to chlorate formation (discussed at the end of this thread, link: http://www.sciencemadness.org/talk/viewthread.php?tid=34429 ).

Note my yield comparison comment.

And, for sure, the sunlight can boost your Vitamin D level and you may actually feel better :).

PHILOU Zrealone - 22-3-2015 at 12:11

Acetone extraction of NaClO3/NaCl mix will also leave the NaCl undissolved!
Yes NaClO3 is many times more soluble than NaCl in aceton and NaClO4 is even more :-)