Anhydrous chlorine generation with TCCA

[ning]

Here's another crackpot idea for the hive to sting. Thinking about the OTC oxalyl chloride idea, and requiring a source of chlorine gas other than Ca(OCl)2, which seems to be impossible to find here, ning was hit by the following idea, regarding the generation of chlorine from TCCA (trichloroisocyanuric acid, trichlorotriazinetrione), which is readily available to ning. Upon further consideration, ning realized that not only would the idea probably work, but it involved NO water production.

Compare:

Ca(OCl)2 + H2SO4 --> CaSO4 + Cl2 + 2 H2O

TCCA + 3 H2SO4 + 3 NaCl --> CA + 3 NaHSO4 + 3 Cl2

As far as ning knows, TCCA reacts with HCl to produce Cl2. TCCA is stable in sulfuric acid (that's how it's purified), and sulfuric acid + salt is the standard HCl generator method. Combine them, and you have a Cl2 generator.
Probably some HCl will come over too. That's no problem for ning, because the chlorination also generates HCl. Not needing a wash bottle is well worth it.

Reaction stoichiometry:

78  g TCCA
60  g NaCl
100 g H2SO4

This would bee enough to chlorinate 15 g ethylene glycol, producing, ideally, 31 g oxalyl chloride.

to produce the same chlorine via the Ca(OCl) method would need:

143 g Ca(OCl)2
100 g H2SO4

ning imagines more sulfuric acid would bee needed to absorb the formed water.

Turns out the mass required is the same, and if it turns out that NaHSO4 can react with NaCl to produce HCl as well, the acid amount could bee reduced.

Thoughts? Is ning barking up the wrong tree here?

[ning]

Is there nobee with an interest or use for chlorine these days? Or who would be willing to use their gassing apparatus to try this?

[Organikum]

I will give it a try soon and post the results. It is of course worth a consideration if trichloroisocyanuric acid cannot be used to do the chlorination you want "in situ". Might be worth a try too. My lung says this would be the most preferable way.

[Aurelius]

Make sure that the solids are intimately (always liked that term) ground together before adding the sulfuric- otherwise you'll probably be getting a lot of HCl instead of your precious Cl₂

[Organikum]

Shouldnt it be a layer of NaCl at the bottom and the TCCA on top? Facing the fact that chlorine is heavier than HCl-gas?

[ning]

Thanks, organikum!

I think maybe mixing or grinding the stuff with a diluent like sand would help. Or, perhaps, dropping the sulfuric acid through a tube to the bottom of the vessel.


Also, I would much prefer to use solid chlorinating agents. However, it appears oxalyl chloride will react with amides/imidines(?). But is this only in basic conditions, or would it happen in acid conditions as well? That is the question. Just adding a little dry HCl or H2SO4 to ethylene glycol and carefully adding TCCA or that funny dichlorodimethylhydantoin might work, if oxalyl chloride only attacks in basic conditions. It would also be much, much more economical with chlorinating agent than the production of chlorine.
Well, chem experts? Does an acyl halide react with an amide or imidine in acidic conditions, or must it be deprotonated?

[Organikum]

dropping the sulfuric acid through a tube to the bottom of the vessel.

Bad idea. This will clog.
Using a KIPP principle apparatus and an excess of NaCl could work.

ADDON:
Good news! I found a procedure describing the production of chlorine by using NaCl/H2SO4 onto MnO2 instead of the ususal HCl onto MnO2. It is told this being advantageous for more chlorine being produced and for the H2SO4 scavenging H2O from the reaction.
So there is little doubt that this will work just fine with TCCA. The only question left is if not TCCA is a too expensive material for this task - MnO2 maybe not everywhere available with ease but if MnO2 isnt, FeO2 is (for coloring cement) and I believe this will work as substitute for MnO2.

Reference:
- Manual of Inorganic Chemistry, Charles W. Eliot and Frank H. Storer, 1876, page 106.

[Organikum]

Experimental:
Dropping conc. H2SO4 onto a mixture of NaCl and TCCA produced mainly HCl and lots of foam and only little Cl2 (as far it was possible to estimate this).
Wettening the TCCA/salt mixture might/should help, also I am not sure in how far the so produced chlorine will be anhydrous - I doubt it.

I guess a little water MUST be present to get the HCl-TCCA to Cl2 going.

Perhaps I give it a try later with a mush of NaCl and TCCA.


Actually the production of chlorine isnt the main problem. The main problem is the production of Cl2 in a steady stream over a longer period of time, safe and without needing permanent attention.

A KIPP?
Further suggestions except "get an cylinder" are highly welcome.
ORG  

[lugh]

According to Experimental Methods in Gas Reactions by Farkus and Melville:

This gas is most conveniently prepared in a pure state by dropping pure concentrated hydrochloric acid on potassium permagnate contained in an evacuated flask. It is washed in permagnate solution, in water (in darkened vessels) and dried with P₂O₅. Four or five fractionations remove the last traces of oxygen (cf. e.g. M.Ritchie and R. G. W. Norrish (Proc.Roy. Soc., A, 140 105(1933))-an impurity which often acts as an inhibitor in reactions of chlorine. M. Bodenstein (Z. phys. Chim. B7, 387 (1930) dispenses with greased traps, and finally purifies his chlorine in an apparatus connected together with glass ungreased taps.

Cheapskate used the same basic techniques as mentioned in the thread starting with

Post 100482 (missing)

(Atomicdog: "Chlorine gas generation", Chemistry Discourse)  

[Organikum]

Permanganate is not easy and OTC in bigger amounts here where I live. FeO2 is and works well with H2SO4 and NaCl. The salt has to be fused - coarse table salt produces mainly HCl-gas. Dishwasher salt comes fused into bigger granules and works ok. (same for MnO2)

The electrolytic production of chlorine is better done with a HCl saturated NaCl solution than with HCl alone. Electrolysing metalsalts, ironchloride or zincchloride ist told to produce quite clean and low-oxygen containing chlorine too.

Dripping dil. H2SO4 onto bleach (or hypochlorite) works better than using HCl.



I can say for sure that - except the KMnO4 method perhaps, which I dont know - no described method in the linked thread will make a bee happy. Many will make her cough mainly. To much water, to much oxygen which is the devil in organic chlorinations...

The TCCA is a new and promising way though.


cough, cough
ORG

[politoxicomania]

Cl₂ can be made in 3  different ways.
The common one is electrolytical oxidaization of Cl^-.
Second way is already mentioned : Oxidization of Cl ^--ions under strong acidic conditions and by the presence of MnO₂.

The third method ist like this :
1 , CaCl(OCl) + 2HCl --> CaCl2 + H2O + Cl2
7 M HCl , CO2 impurities

and this is for experts:
 XeCl₄--> XeCl₂+ Cl₂--> Xe + 2 Cl₂


If u want to know more about generating gases,
look here:

Post 468552

(politoxicomania: "Gas SWIM needs", Chemistry Discourse)