Chlorine water chemistry question

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brad.maynes

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Okay, I will fully admit that I am being an overly-anal retentive ex-chemistry major here, but ... when you pre-boil your liquor, does that remove all chlorine such that when I am considering salt (generally, not NaCl) additions, I can assume that Cl is at 0?

Not sure if this is the right spot for this question ...
 
Yes boiling would remove all free chlorine. Wouldn't it be more economical to just filter the chlorine out using an activated charcoal filter. Thereby also removing the chlorine byproducts.

Why are you considering adding salts?
 
Also, be sure to check that your city water doesn't contain chloramines, which to the best of my knowledge cannot be boiled out but must be treated.
 
As has been suggested, water co's add amonia to the chlorinated water which produces chloramines. This keeps the water fresh like chlorine but chloramines are more stable than chlorine, they don't readily gas off and are effectively fixed into the water (this is the reason the water co's do it).

Carbon filters are great at removing these, alternatively you can fill a spare bucket with your brewing water and add 1/2 a crushed campden tablet per 6 us gals. (you don't need to be too accurate, if you add too much it theoretically helps to combat oxidation).
 
brad.maynes said:
Because the water in Ann Arbor is alarmingly clean, e.g. free of salts. We're talking about halfway between Pilsn water and London water.
That sounds just about perfect for most any kind of beer! Pilsen water is extremely soft, while London's is fairly hard. Something in between would probably do just fine for anything but a very light beer.
 
DAAB said:
As has been suggested, water co's add amonia to the chlorinated water which produces chloramines. This keeps the water fresh like chlorine but chloramines are more stable than chlorine, they don't readily gas off and are effectively fixed into the water (this is the reason the water co's do it).

Carbon filters are great at removing these, alternatively you can fill a spare bucket with your brewing water and add 1/2 a crushed campden tablet per 6 us gals. (you don't need to be too accurate, if you add too much it theoretically helps to combat oxidation).

According to everything I've read regular Carbon Filters will not remove chloramines, unless it is a certain type filter.

I found this here: http://www.thefilterguys.biz/chloramine_filters.htm

Catalytic Granular Activated Carbon CGAC made from Bituminous Coal is the most effective means of removing chloramines. High quality carbon block filters also remove Chloramines but CGAC is the most effective. The catalytic reduction capacity of all carbon filters is greatly reduced by chloramines as opposed to chlorine. This reduced capacity makes some carbon filters almost useless for chloramine reduction. CGAC followed by RO and DI seems to be the best non-chemical intensive method of treating chloramines. We have put together an array of filters, which we consider to be the best solution for chloramine reduction.



here's a paste from Wikipedia:

Home brewers use reducing agents such as sodium metabisulfite or potassium metabisulfite to remove chloramine from brewing liquor as it, unlike chlorine, cannot be removed by boiling (A.J. DeLange). Residual sodium can cause off flavors in beer (See Brewing, Michael Lewis) so potassium metabisulfite is preferred.
 
According to everything I've read Carbon Filters will not remove chloramines, unless it is a certain type filter.
Try reading something else other than wkipedia then:D

I knew I should have written 'GAC' filter (granulated activated carbon).;)

btw I saw someone mention the amount of sodium sodium met' adds when added to neutralise chlorine, I can't remember the figure but is is miniscule.

On the other hand some GAC filters are combination GAC resin filters which remove calcium ions and exchange them for sodium ions, this sodium addition is enough to cause problems...I speak from first hand experience.
 
abracadabra said:
Maybe I'm being technical here but there's a difference between remove and reduce.

Nope, you're absolutely right they don't remove 100% but it was easier to write "remove" rather than writing "reduce to a level acceptable for brewing" but now I have had to go and do it anyway...that's what I get for being lazy I guess:rolleyes:.
 
DAAB said:
Nope, you're absolutely right they don't remove 100% but it was easier to write "remove" rather than writing "reduce to a level acceptable for brewing" but now I have had to go and do it anyway...that's what I get for being lazy I guess:rolleyes:.

What's "acceptable" to you is a subjective term. I'm simply trying to point out that before anyone buys just any old carbon filter they should see if it has much or any real effect on chloramines. As all carbon filters are not created equal.
 
Again, you're right, I should have specified GAC filters rather than assuming that people would automatically know this.
As you say, acceptable is a subjective term, but GAC filters are considered by many homebrewers, craftbrewers and commercial brewers in the UK and I believe commercial brewers in the US to be an acceptable method of chloramine removal for brewing.
 
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