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Re: Speaking of Chloramine...

Bob wrote:
> As long as the subject has been mentioned, how does Choramine work, anyway?
> Chemically, I mean.  Both NH4 and Cl are negative ions, right?  So, how do
> they get chemically bonded to one another?  Inquiring minds want to know.

I don't claim to understand it completely, but here's a reference that I
found while doing research:

"Chloramines are typically generated on-site by the addition of ammonia (NH3)
to water containing free C12 (HOCl or OCl depending upon the pH of the water).
The optimum reaction pH is on the alkaline side, pH 8.4 
(i.e., NH3 (aq) + HOCI  NH2Cl + H2O) 

Three forms of chloramine can result as well as undesirable but unavoidable
interference reactions (#4 below).

1) NH2Cl Monochloramine
2) NHCI2 Dichloramine
3) NCl3  Trichloramine
4) RNHCl Organic Chloramine

Organic chloramines cannot be distinguished from the other forms of chloramines
with standard methods of chloramine analysis.

Chloramines are not highly disassociated (in other words only minimally ionic). 
That fact and their low molecular weight make them difficult to remove via RO
(discussed in more detail below). The monochloramine form is the best biocide, 
and as is noted, is the dominant specie at pH 7 and greater."

The complete text of this is available at:

Chuck Gadd