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Sauron
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[*] posted on 7-4-2009 at 21:46
Chlorosulfonic acid


This substance pops up in threads from time to time.

ClSO2OH It is the half acid chloride of sulfuric acid, or may also be regarded as the mixed anhydride of sulfuric and hydrochloric acids.

The usual preparation is done by passing a SLOW stream of DRY HCl gas into 65% oleum, until no more HCl is absorbed. The resulting mix of 100% H2SO4 and chlorosulfonic acid can then be fractionated. Obviously this must be done with exclusion of all moisture.

The hassle is 65% oleum is expensive while commercial chlorosulfonic acid is cheap.

The other hassle is that the reaction is highly exothermic, which is why the passage of HCl needs to be quite slow. The pot should be kept close to room temperature. Any overheating and SO3 can distill out of the mix. Until addition is complete, the condenser should be set for reflux.

I found an alternative prep that I like better:

"Chlorsulphonic acid, SO 2 CI. OH, first prepared by A. Williamson (Proc. Roy. Soc., 1856, 7, p. 11) by the direct union of sulphur trioxide with hydrochloric acid gas, may also be obtained by distilling concentrated sulphuric acid with phosphorus oxychloride:

2 H 2 SO 4 +POCl 3 =2 SO 2 ClOH+HCl+HP0 3

(1911 Britannica, monograph on sulphur)

Since POCl3 can be prepared at high temp. from P2O5 and NaCl, this is practical and cheap.

[Edited on 8-4-2009 by Sauron]




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[*] posted on 7-4-2009 at 23:04


It's also formed in the hydrolysis of sulfuryl chloride SO2Cl2, but I suspect that controlling the reaction is difficult to impractical as I've found few references to that process.
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[*] posted on 7-4-2009 at 23:40


I was wondering about that, because SO2Cl2 is of course the the acid dichloride of H2SO4, or to rwrite more appropriately SO2(OH)2.

So chlorosulphonic acid is the half chloride, and we couldf call sulfuryl chloride "chlorosulfonyl chloride" if we wished.

My recollection is that SO2Cl2 is not hydrolyzed by cold water but forms a hydrate. So, you would sure haave to expect that one mol well stirred SO2Cl2 treated with one mol cold water must eventually as it rises to ambient and the exotherm kicks in, hydrolyze one and only one Cl to produce chlorosulfonic acid one mol and a mol of HCl.

I am inclined to try this as SO2Cl2 is easier to make than POCl3.

My source re the hydrate is Merck, let me have another look.

"Slowly dec by water, forming H 2 SO 4 and HCl. With ice-cold water it forms a hydrate, SO 2 Cl 2 .15H 2 O, resembling camphor in appearance."

So not ice-water. Cool or room temp. water.

[Edited on 8-4-2009 by Sauron]




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[*] posted on 8-4-2009 at 00:05


"With ice-cold water it forms a hydrate, SO2Cl2.15H2O, resembling camphor in appearance." I beleive this is an extract from the Merck Index from google. It would have been better if the stoichiometry was 1:1, as then the hydrate could be formed and then heated to possibly leave chlorosulfonic acid. Perhaps adding 1 mole of hot water to 1 mole of warmed sulfuryl chloride can lead to chlorosulfonic acid (assuming it doesnt form the hydrate... shouldnt be a problem at elevated temperatures). Is there anything to suggest that the half hydrolysed sulfuryl chloride (chlorosulfonic acid) will hydrolyse faster than the unreacted sulfonyl chloride?
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[*] posted on 8-4-2009 at 00:20


That's what I was wondering, too. An alternative might be a 1:1 mix of SO2Cl2 and H2SO4, which if it reacts could give 2 moles of SO2ClOH, or HCl and SO3 which would seem to turn around and react to form SO2ClOH.

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[*] posted on 8-4-2009 at 03:20


That's a pregnant idea as well. The disproportionation makes good sense, only thing is that the conc H2SO4 better be 100% or a low % oleum (<5%) or you will lose some product to H2O.

With a low % oleum you can add dry HCl to the product to convert aby remaining SO3 to chlorosulfonic.

DJF90, I think chlorosulfonic acid reacts, uh, vigorously with water and I thought sulfuryl chloride did too. Merck Index says not. I got that off the Merck Index 12th Ed. CD and I also have the hardcopy book. Google? Who needs it?

Sometime before 1980 I did a chore disposing of aggressive reagents down the drain in a hood at the SURD labs in New Orleans (USDA, FDA) and these included chlorosulfonic acid, oleum, sulfuryl chloride as I recall, maybe some fuming nitric as well. (They would not let me haul them away damn it!). But at this late date three decades on I do not remember which reagents made the most fuss when flushed.


[Edited on 8-4-2009 by Sauron]




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[*] posted on 8-4-2009 at 04:09


SO2Cl2 does not react with water at room temperature. I have some of this liquid and it actually is fairly tame stuff, not nearly as reactive and energetic at SOCl2 with water. It only very slowly dissolves in cold water (takes hours for dissolving a big drop of this liquid).

When SO2Cl2 is added to hot water, then it dissolves, giving HCl and H2SO4 and this reaction takes minutes. I have a book from Vilano (old German pre-WWII book about preparative chemistry) which even suggests cleaning SO2Cl2 by shaking it with cold water and then separating the layers which are formed and carefully distilling off the lower-boiling SO2Cl2. According to this book, SO2Cl2 is not capable of forming SO2Cl(OH). It either reacts to complete hydrolysis giving H2SO4 or it does not react at all. Chlorosulphonic acid is MUCH more reactive than SO2Cl2.




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[*] posted on 8-4-2009 at 04:42


Ism't that Vanino's book?

It makes no obvious sense for SO2Cl2 not to be halfway hydrolyzable.

Here's a reaction of chlorosulfonic acid to give sulfuryl chloride, catalyzed by mercuric sulfate, obviously a disproportionation. The only possible chlorine source is the starting material itself.

2 ClSO2OH -> SO2Cl2 + H2SO4

or more clearly

2 Cl-SO2-OH -> Cl-SO2-Cl + HO-SO2-OH

Logically, H2SO4 ought to chlorinate to either chlorosulfonic acid or sulfuryl chloride, but I have never heard of such a reaction.

We know SO2Cl2 will hydrolyze to H2SO4 and HCl (albeit slowly)

The less than obvious explanation is likely kinetics, ClSO2OH is hydrolyzed so much faster than SO2Cl2 that no chlorosulphonic acid remains when all water is consumed.

a mol of sulfuryl chloride is 134 g.

A mol of water is only 18 g

If SO2Cl2 cannot be hydrolyzed to the half chloride, but only to the acid, then mixing one mol H2O with one mol sulfuryl chloride and waiting till reaction is complete will produce a 1:1 mixture of H2SO4 and unreacted SO2Cl2 with one mol HCl either dissolved or evolved. A simple enough experiment to design and perform, isn't it?

I think a look in Mellor is apropos.

In hindsight I ought to have resorted to ACTOITC from the start

Here is the section on halosulfonic acids, with references.

[Edited on 8-4-2009 by Sauron]

Attachment: halosulfonic acids.pdf (270kB)
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[*] posted on 8-4-2009 at 05:57


And here, sulfuryl halides. Again with references.

Attachment: sulfuryl halides.pdf (401kB)
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[*] posted on 8-4-2009 at 06:26


I find it strange that sulfuryl chloride reacts so slowly with water, while it reacts violently with alcohols like methanol.
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[*] posted on 8-4-2009 at 07:51


According to Mellor, Michaelis reports that chlorosulfonic acid is the first hydrolysis product of SO2Cl2. This suggests that the stoichiometric reaction of equimolar H2O and SO2Cl2 at ordinary temperatures (e.g. above ice cold!) ought to be ClSO2OH.

Mellor also reports that equimolar H2SO4 and SO2Cl2 do give 2 mols ClSO2OH so it is really unnecessary to suss out the hydrolysis.

According to O.Ruff, refluxing chlorosulfonic acid over catalytic mercuric sulfate quantitatively decomposes iy into H2SO4 and SO2Cl2, this is the reverse of the reaction immediately above.

[Edited on 8-4-2009 by Sauron]




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[*] posted on 8-4-2009 at 08:24


Plus in the pdf you uploaded there is a reference of McKee & Salls that implies using this route on a commercial scale.

But still there seems to be a number of contradictions in these notes.

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[*] posted on 8-4-2009 at 17:05


Someone should put it to the test.

It would be very convenient if SO2Cl2 can be made into ClSO2OH. I'm inclined to trust Mellor's, but this should be confirmed. SO2Cl2 is so easily made that it would be a great source of chlorosulfonic acid, if indeed this works.





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[*] posted on 8-4-2009 at 18:34
More Take from Mellor


A more careful look at Mellor reveals a larger number of preps of chlorosulfonic acid.I group these into three categories:

Disproportionation of SO2Cl2 and H2SO4

Chlorination of conc (pref 100%)H2SO4

This is by Cl2 itself, or PCl3, PCl5, POCl3, by S2Cl2 or SCl2, by SOCl2, and by P2O5 and 100% H2SO4 with passage of HCl gas. The latter is clearly the in situ formation of POCl3.

Stoichiometric Hydolysis

Hydrolysis of Pyrosulfuryl Chloride

I mention this merely for sale of thoroughness,

Controlled hydrolysis of sulfuryl chloride.

It remains now to look at the references and see what is what. But so far it does appear that chlorosulfonic acid behaves consistent with its position as halfway between H2SO4 and SO2Cl2.

Chlorosulfonic acid is assymmetrically substituted, with an electronegative halogen on one side and an electron rich hydroxyl on the other and an electron rich S(=O)2 center. In this light the disproportionation reactions are not at all surprisong since symmetrical products are obtained

2 ClSO2OH <-> H2SO4 + SO2Cl2 (catalyzed to right by HgSO4)

I also see a unity between the half hydrolysis of SO2Cl2 by the addition of a single mol H2O (avoiding formation of the hydrate by not using very cold water) and the disproportionation.

This can only proceed in one of two ways:

a) by formation of one mol ClSO2OH and one mol HCl gas

b) by the formation of 0.5 mol H2SO4 1 mol HCl gas leaving 0.5 mol SO2Cl2 unreacted. The equimolar sulfuric acid and SO2Cl2 then disproportionate to 1 mol ClSO2OH

In both cases the final product is the same.

Explanation (a) is simpler and so favored by Occam's Razor.

Carefully designed p-chem experiments can tell which is really happening.


[Edited on 9-4-2009 by Sauron]




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[*] posted on 9-4-2009 at 22:53


I have done a simple experiment, and it really seems that no SO2Cl(OH) is formed. I took appr. 1 ml of 96% H2SO4 and appr. 1 ml of SO2Cl2. The liquids do not mix, the SO2Cl2 forms a layer on top of the sulphuric acid. When the liquids are shaken vigorously, then a turbid suspension is formed, which in a few minutes separates into two layers again. I allowed the liquids to stand for many hours and in the meantime I vigorously shaked the liquids but the result is the same all over again. I did not yet try heating the mix, I still have the liquids standing in the test tube, forming two layers.

Another interesting experiment would be doing the reverse, taking SO2Cl(OH) and heating this somewhat. Does it form a two-layer system, giving H2SO4 and SO2Cl2? I do not have SO2Cl(OH) though, so I cannot perform the experiment.

@Sauron: You were right about the name of the author of the book. I misspelled his name. This book indeed tells that a good way to clean SO2Cl2 is shaking it with cold water and then carefully distilling it. Preparation of SO2Cl2 is from equimolar streams of SO2 and Cl2 over camphor.




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[*] posted on 9-4-2009 at 23:35


Heating is necessary for the disproportionation reaction in either direction, stirring ought to speed things up somewhat but at RT this will take forever.

I would expect the reaction to be slow but eventually the two layers will merge and remain merged and you will have chlorosulfonic acid

The reverse reaction requires Hg or HgSO4 catalyst. Reflux chlorosulfonic acid over a little HgSO4 and you will thwn bw able to fractionate off SO2Cl2 and H2SO4 will remain in the pot.

Why not read the original papers? One line in Mellor, much less my recitation, tells little.

If you say nay you are going against some giants like Ruff and Michaelis. Bad idea!

All your experiment did was show that the reaction is not rapid at ambient and I could have told you that without dirtying a test tube.




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[*] posted on 10-4-2009 at 00:02


Quote: Originally posted by Sauron  

2 ClSO2OH <-> H2SO4 + SO2Cl2 (catalyzed to right by HgSO4)

....

Heating is necessary for the disproportionation reaction in either direction, stirring ought to speed things up somewhat but at RT this will take forever.

The reverse reaction requires Hg or HgSO4 catalyst. Reflux chlorosulfonic acid over a little HgSO4 and you will thwn bw able to fractionate off SO2Cl2 and H2SO4 will remain in the pot.

Why not read the original papers?

Unfortunately I also did not read the original papers.
I just wanted to clarify a little detail. Catalysts do not dictate the equilibrium constant as one might conclude from your remarks above. I would dare to guess that in the example of SO2Cl2 preparation from ClSO3H the reaction is driven toward the product by distilling it off while HgSO4 only serves to speed up the equilibration (and not to change the direction). In other words, the same catalyst should speed up the formation of ClSO3H from a mixture of SO2Cl2 and H2SO4 (Woelen, if you have some HgSO4 or HgCl2, could you please add it to that test tube?).

PS: The reaction of SO2Cl2 with nucleophilies like H2O, H2SO4 and so on is slow because S-Cl bonds are not polarized in the same direction as in SOCl2 (ClSO2- and -Cl groups have inductive effects of similar strength; I think the bond polarization is even slightly the reverse of that in SOCl2). For the same reason SO2Cl2 is so good in radical chlorinations (the S-Cl bond easily breaks homolyticaly while in SOCl2 it can not).




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[*] posted on 10-4-2009 at 00:25


Quote: Originally posted by Nicodem  
I would dare to guess that in the example of SO2Cl2 preparation from ClSO3H the reaction is driven toward the product by distilling it off while HgSO4 only serves to speed up the equilibration (and not to change the direction). In other words, the same catalyst should speed up the formation of ClSO3H from a mixture of SO2Cl2 and H2SO4 (Woelen, if you have some HgSO4 or HgCl2, could you please add it to that test tube?).


That is the definition of a catalyst. A catalyst can never catalyse a reaction "in one direction". A catalyst always speeds up the formation of a thermodynamic equilibrium, but does not influence its equilibrium constant. Only the circumstances of the reaction, such as temperature and especially relative concentrations of the reactants, dictate whether a reaction goes into one or the other direction.

For the case of the sulfuryl chloride-sulfuric acid-chlorosulfonic acid system, I remember reading in Sartori's "The War gases" in the chapter about sulfuryl chloride preparation that simply heating chlorosulfonic acid under pressure in an autoclave causes it to disproportionate quantitatively into H2SO4 and SO2Cl2 (which separate into two phases)- and this is WITHOUT distilling off the SO2Cl2. It is also stated that HgSO4 causes this disproportionation to happen during atmospheric pressure reflux. No mention is made about having to continuously remove the SO2Cl2.

So I dare to guess that the thermodynamic equilibrium of the
2 ClSO3H <----> SO2Cl2 + H2SO4 reaction lies far at the right side, and that it is not possible to prepare ClSO3H from SO2Cl2 without very special measures to remove ClSO3H or H2SO4 from the equilibrium as fast as they are formed.




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[*] posted on 10-4-2009 at 01:21


I said nothing about having to strip the SO2Cl2 off as formed, because Mellor and AFAIK his citations say nothing of the sort. I also recently reread Sartori on these compounds, and posted about it and yes, I saw the pressure disproportionation, but as so few of us own autoclaves I did not mention it.

People think ill of me if I keep badhing them in the face with my Patt 1 L.

Since the point of the thread is prep of chlorosulfonic acid, and it is fairly ridiculous to make readily preparable SO2Cl2 from more difficult to prepare ClSO2OH (unless one can buy it, or has ready access to a cheap supply of 65% oleum) I was focusing on the most facile routes to ClSO2OH that do not rely on SO3, oleum etc. I have 4 Kg 65% oleum but I will not give any of it up to make chlorosulfonic acid!

The most facile rotes appear to be

Hydrolysis of SO2Cl2 with a very limited amount of water and NOT ice cold water

chlorination of conc H2SO4 by Cl2 or any of the usual chlorination agents

Disproportionatin of SO2Cl2 and H2SO4

The lit so far as I have looked to this point in time does not mention Hg or HgSO4 catalysis of this. However the catalysis of the reverse reaction is documented and certainly implies it, in fact requires it.

ClSO2OH refluxes at 153 C so the reflux condeenser recommended is an air condenser. As So2Cl2 has a bp of 69-70 C so it WILL flash off and will pass the air condenser so provision had better be made to condenser and collect it.

You could of course use a coolant at > 50 C and thus reflux both of these, but recirculating heaters are relatively rare and costly compared to recirculating chillers. I would say, 60 C would be about right.

H2SO4 is just goint to stay in the pot.

The reflux temp ought to drop as the chlorosulfonic acid diminishes and sulfuryl chloride increases. So the heating can be reduced and normal cooling commenced. Caution, though as you do not want to crack a condenser at the jacket when reluxing these nasties.



[Edited on 10-4-2009 by Sauron]




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[*] posted on 10-4-2009 at 02:16


Quote: Originally posted by Sauron  

The most facile rotes appear to be

Hydrolysis of SO2Cl2 with a very limited amount of water and NOT ice cold water

I don't think this is possible due to the reasons I explained in my previous post. You would only obtain a mixture of H2SO4 and SO2Cl2, but no ClSO3H.
Quote:
chlorination of conc H2SO4 by Cl2 or any of the usual chlorination agents

You can not oxidise H2SO4 any further with Cl2. The sulfur is already at its highest oxidation state.
Quote:
Disproportionatin of SOCl2 and H2SO4

Assuming you meant SO2Cl2 when you wrote SOCl2 (in the sense of previously discussed disproportionation reaction)... Unfortunately the information that Garage chemist just provided indicate that at least at a higher temperature the equilibrium lies toward SO2Cl2+H2SO4 rather than toward ClSO3H. It might be the opposite at room temperature, but unless someone provides a reference, or Woelen demonstrates it experimentally, we can only guess. I also thought it would be toward ClSO3H, that is why I said that the procedure most likely involved distilling off SO2Cl2 as it formed, but it seems this is not the case.

Quote:
The lit so far as I have looked to this point in time does not mention Hg or HgSO4 catalysis of this. However the catalysis of the reverse reaction is documented and certainly implies it, in fact requires it.

Like I said before and like Garage chemist explained even more in depth, there is no such thing as changing direction of the same reaction by different catalysts. The catalyst has absolutely no influence whatsoever on the equilibrium constant. You can not catalyse a "reverse reaction", you can only catalyse the reaction, because it is exactly the same reaction. All a catalyst can do is increase the reaction rate (that's what it is used for). For example, see http://en.wikipedia.org/wiki/Catalysis . You can not fight with thermodinamics without energy.

[Edited on 10/4/2009 by Nicodem]




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[*] posted on 10-4-2009 at 02:56


Nicodem I posted an entire subchapter from Mellor with references and these claim that controlled hydrolysis of SO2Cl2 to chlorosulfonic acid DOES work, that chlorination of conc H2SO4 DOES work, with Cl2, PCl3, PCl5, POCl3, SOCl2 (yes thionyl chloride) anyway which are I what I called the usual suspects. Clealrly these are not disproportionation reactions, but chlorinations.

The same text and refs also state that SO2Cl2 + conc H2SO4 -> 2 ClSO2OH.

You are taking an offhand experiment by woelen without any serious effort to learn what conditions are required, and a comment from gara chemist, and then demanding references when I have already provided a raft of them. Why don;t you bother reading Melloe on chlorosulfonic acid and Mellor on sulfuryl chloride. There they are attached upthread.

You say H2SO4 cannot be chlorinated but asmall army of eminent chemists teach otherwise. You may want to reexamine your premise.

I have 7 volumes of Mellor sitting on my desk awaiting dissection and scanning. The exerpts above are not from these or the other 7 volumes I have purchased and not yet received, they are from Mellow's Sulfur chapter out of Volume X which has long been in the forum library. I can't help wondering why I am scanning 17,000 pages if no one wants to read even the ones we already have? Very disappointing!




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[*] posted on 10-4-2009 at 03:06


Further. re hydrolsis of SO2Cl2:

Take ONE mol SO2Cl2 and add ONE mol water at ambient with stirring.

TWO mols water would be required to completely hydrolyze SO2Cl2 to H2SO4 + Hcl (g)

Therefore, there are two and only two possibilities

I am repeating myself but you seem to have missed this

A. ONE mol of the half hydrolysis product form ClSO2OH

B. HALF a mol H2SO4 and HALF a mol HCl gas form and the other half of the SO2Cl2 is untouched.

So, we have the conditions for the disproportionation to same product as (A).

A deeper look at Mellor's sources will establish time and temp (hopefully)

It is necessary to avoid use of water cold enough to form the monohydrate or the 15H1O hydrate which are stable camphorlike solids.




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[*] posted on 10-4-2009 at 03:18


Quote: Originally posted by Sauron  
Nicodem I posted an entire subchapter from Mellor with references and these claim that controlled hydrolysis of SO2Cl2 to chlorosulfonic acid DOES work, that chlorination of conc H2SO4 DOES work, with Cl2, PCl3, PCl5, POCl3, SOCl2 (yes thionyl chloride) anyway which are I what I called the usual suspects. Clealrly these are not disproportionation reactions, but chlorinations.

Maybe I should have said that I'm not interested in the topic. The only reason I posted in this thread was to comment on your way of treating thermodinamic rules. Just to clarify a certain thing, rather than contribute to the topic.
Anyway, while I'm here I will also add that there is absolutely no way you can get ClSO3H from only Cl2+H2SO4 unless you reduce Cl2 in situ with something like phosphorous. And I'm not even going to check the reference you mention (what for?). The other reagents you mention (PCl3, PCl5, POCl3, SOCl2) are something completely different and it is expected they would give ClSO3H from H2SO4. But with Cl2+H2SO4 where are the Cl atoms going to take the electrons from?
About the H2SO4/SO2Cl2/ClSO3H equilibrium. I thought, we already concluded that the reaction is indeed working and several sources conclude so. I was not disputing that, I only wanted to say that I have yet to see a reference claiming the equilibrium is toward ClSO3H.
For example, in the book Chlorosulfonic Acid there is no mention of this reaction being a preparative method. It does list only the methods already mentioned in this and other threads of the forum (page 1):
Quote:
Chlorosulfonic acid was first prepared by Williamson[1] in 1854 by the action of phosphorus pentachloride on concentrated sulfuric acid and later[2] by the direct action of hydrochloric acid on sulfuric trioxide. Other methods of preparation include: distillation of fuming sulfuric acid (oleum) with phosphorous pentoxide in a stream of gaseous hydrogen chloride; the action of phosphorus trichloride or oxychloride, chlorine, thionyl chloride, or sulfur monochloride on concentrated or fuming sulfuric acid; passing a mixture of sulfur dioxide and chlorine into glacial acetic acid; or reaction of carbon tetrachloride with fuming sulfuric acid.[2]

[1] AW. Williamson, Proc. R. Soc. London, 1854, 7, 11.
[2] AW. Williamson, J Chem. Soc., 1857, 10. 97.
[3] KE. Jackson, Chem. Rev., 1939, 25, 83.

(I bolded the method I find most suitable for an amateur lab, especially since it has the added bonus of making an equivalent of AcCl as a side product)

Furthermore on the page 3 it discusses this disproportionation as directed toward SO2Cl2+H2SO4.




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[*] posted on 10-4-2009 at 03:50


Nicodem, in the very passage you quote, a variety of chlorinating agents are stated to work on H2SO4 and also Cl2. Also SO2Cl2.

Those are chlorinations. So now you merely scoff at Cl2 doing the job? But are too disinterested to bother checking the references.

Well, I am not disinterested and I will dig out the references.

SO2 and Cl2 obviously form SO2Cl2 in situ and AcOH is a known catalyst for this reaction - not as popular as GAC or camphor. I saw nothing about ClSO3H from this.

I did see a ref to imperfectly dried Cl2 and wet SO2 over Pt black at red heat forming ClSO3H. What is this but formation of SO2Cl2 and partial hydrolysis by steam

In reciting what Mellor said on the disproportionation reaction I may have expressed myself poorly, but I was accurately stating the text. So when I said that no mention was mae of catalyst in the formation of ClSO2OH from SO2Cl2 and that in the decomposition/disproportionation of ClSO3OH to SO2Cl2 and H2SO4, Hg or HgSO4 is employed, I did not mean to state that the former would not work with selfsame catalyst, nor that the latter would not work without that catalyst. OBVIOUSLY these are the same reaction with a double headed arrow, and equally obviously the catalyst does not dictate the reaction, or the rate constant, merely accelerates it.

But till proven otherwise I assume that since Mellor states that BOTH reactions work, that this is indeed the case.

If ypu regard this as insufficient obeisance to the gods of thermodynamics, then, burn me for a blasphemer.



[Edited on 10-4-2009 by Sauron]




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[*] posted on 10-4-2009 at 04:32


Interesting that the book on chlorosulfonic acids lists passing a mixture of sulfur dioxide and chlorine into glacial acetic acid as a method of preparation, as that is given elsewhere as a means of preparing sulfuryl chloride, with the acetic acid essentially unchanged.

So either some chemical relationships changed when Queen Vicky passed on, or this group of reactions have a more complicated relationship that the references lead one to first believe.

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