[FeLiXe]

hi could someone help me with this:

I am wondering if hypochlorite that is released at an industrial plant would react with hydrocarbons to form  organic halogenated compounds. I don't think so. The only thing I could think about is addition to an alkene to form a 1-hydroxy-2-chloro-compound that will soon become a diol. And the chlorine is released as chloride. Is that true? Or is it possible that chlorine remains in the organic molecule?

thanks

[dls]

hi could someone help me with this:

I am wondering if hypochlorite that is released at an industrial plant would react with hydrocarbons to form  organic halogenated compounds. I don't think so. The only thing I could think about is addition to an alkene to form a 1-hydroxy-2-chloro-compound that will soon become a diol. And the chlorine is released as chloride. Is that true? Or is it possible that chlorine remains in the organic molecule?

thanks

Many sewage treatment plants add chlorine.  Depending on the pH this may take the form of hypochlorite or its acid.  This can react with double bonds, as you stated, but will also react with primary and secondary amines and amides.  A similar process occurs in swimming pool treatment, except that the chlorine is used up by bacteria, proteins and urea.

[lavoisier]

FeLiXe, in principle I wouldn't exclude that this could happen.
Hypochlorite is easily converted into molecular chlorine below a given pH (sorry, I am to lazy to go and check what pH it is...). Chlorine can add to double bonds yielding fairly stable dichlorinated compounds. Under some conditions, it can also chlorinate alkanes.
It's all about the probability of these conditions to occur, but we're not talking about manufacturing these compounds, are we?

For your second question, I know books give the impression that haloalkanes are exceedingly reactive molecules, and you can't mix them with traces of water without getting alcohols and stuff...
After quite some years of practice of organic chemistry, I dare to say that they are pretty much unreactive (especially chlorides), unless you force them to react. 1,2-dichloroetane is used as a solvent for reactions such as reductive amination, where you have fairly basic and nucleophilic species around, and you can do the work up with water and base with no problem at all. And what about dichloromethane?

Conclusion: I think the formation of traces of chlorinated hydrocarbons from is possible under the conditions you specified, and they'd probably be stable enough to be detected, i.e. they wouldn't be easily hydrolysed in the absence of strong nucleophiles.

[FeLiXe]

thanks a lot

I did not think about so many things that could happen. It seems like part of the OCl will chlorinate hydrocarbons but most of the hypochlorite will not react. but actually even if hypochlorite would react quantitatively, the amount of chlorinated hydrocarbons would stay below the limit (but close to it).

[dls]

Hypochlorite is more likely to react with amine compounds in the water.  This could be from urea, bacteria and amino acids/proteins.  That's why and how they chlorinate swimming pools.
dls