Salt in Liquid Chlorine?

peacefulkancer

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Aug 5, 2013
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So I went to the pool store to pick up some stabilizer and of course they want to test your water. I said I was OK, but thanks anyways. I then wanted to know their price on liquid chlorine and he was saying that he wasn't a fan of it... because it had salt in it.

I am new to all of this.................

..... but I've never heard that liquid chlorine had salt in it. If it does, then it must be a negligible amount.

So all I could think about was... of course he doesn't like liquid chlorine. He likes tablets... because tablets generally throw other things off like pH or CH... which in turn causes you to come back and buy more of his products. All of this of course was after he tested someone's water in front of me, of course telling them that their water was about half a day away from being a Florida Everglade Swamp. For granted, it may have been... since their chlorine was zero.

Anyways, am I missing something on the chemistry lesson here, does liquid chlorine have salt in it... and if so... how much?
 

chem geek

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Mar 28, 2007
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Chlorinating liquid and bleach have salt in them because of the Chlor-Alkali process that makes the chlorine. Electrolysis similar to what is done in a saltwater chlorine generator produces chlorine gas (except that this is extracted as a gas and not just dissolved in water). This is then combined with a solution of sodium hydroxide that is also produced from the electrolysis. So you mix them and get:

Cl2(g) + NaOH ---> NaOCl + NaCl
Chlorine Gas + Sodium Hydroxide ---> Sodium Hypochlorite + Sodium Chloride

For every 10 ppm Free Chlorine (FC) in chlorinating liquid or bleach, there is also around 8-9 ppm salt. When the chlorine gets used/consumed, there is another 8-9 ppm salt for a total of 17 ppm salt.

ALL sources of chlorine result in salt, but chlorinating liquid and bleach (as well as lithium hypochlorite) add additional salt when you add the chlorine. Of course, other sources of chlorine add other things than salt. Cal-Hypo adds calcium increasing Calcium Hardness (CH) while stabilized chlorine (Trichlor and Dichlor) add Cyanuric Acid (CYA). The CH and CYA that are added are much more problematic than the salt that is added from chlorinating liquid or bleach.
 

peacefulkancer

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Chandler, AZ
Chem geek I was just writing up how NaClO when mixed in water would yeild Cl and Na (and others)... but not directly NaCl. I am guessing that once the Cl is used that it recombines to make NaCl... which is how the whole SWG system loop runs in a way.

In either case... I think my point was that the guy is shunning liquid chlorine because of a negligible amount of salt... in favor of tablets that spike CYA and CH which keeps you in his store.
 

Donldson

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Jun 12, 2009
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chem geek said:
For every 10 ppm Free Chlorine (FC) in chlorinating liquid or bleach, there is also around 8-9 ppm salt. When the chlorine gets used/consumed, there is another 8-9 ppm salt for a total of 17 ppm salt.

ALL sources of chlorine result in salt, but chlorinating liquid and bleach (as well as lithium hypochlorite) add additional salt when you add the chlorine. Of course, other sources of chlorine add other things than salt. Cal-Hypo adds calcium increasing Calcium Hardness (CH) while stabilized chlorine (Trichlor and Dichlor) add Cyanuric Acid (CYA). The CH and CYA that are added are much more problematic than the salt that is added from chlorinating liquid or bleach.
To this I will only add that salt doesn't become a problem until it gets in to the several thousand ppm range. CH can become a problem in the several hundred range, and CYA starts to become a problem when it rises over 50 (for non-SWG pools). I think I will stick with liquid myself, far less draining involved.

If you continue to frequent that pool store, be sure to take everything with a grain of salt. Um, pun not intended :cool:
 

Patrick_B

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Jun 7, 2011
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peacefulkancer said:
Oh I forgot to mention, with the people before me he was fanning the idea of mandatory draining of pools every 2 years - "that is just the way it is."
He is right. When you use Dichlor/Trichlor as a sole or major source of Chlorine all the time you'll have to drain to get your Cya back down to proper levels.
:-D
 

peacefulkancer

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Chandler, AZ
Brushpup said:
peacefulkancer said:
Oh I forgot to mention, with the people before me he was fanning the idea of mandatory draining of pools every 2 years - "that is just the way it is."
He is right. When you use Dichlor/Trichlor as a sole or major source of Chlorine all the time you'll have to drain to get your Cya back down to proper levels.
:-D
Yep, exactly.
 

Toesinsand

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Nov 5, 2013
27
Houston, Texas
peacefulkancer said:
Oh I forgot to mention, with the people before me he was fanning the idea of mandatory draining of pools every 2 years - "that is just the way it is."
Dumping the pool every two years would have been a deal for me back when I used Trichlor. I was dumping about a quarter of the water every month just to keep the CYA levels around 60. Lower than that was impossible. I was spending as much on water then as I am on liquid chlorine now. Then there was all the stuff the pool store sold me on top of the tablets to keep algae from exploding. PhosFree, algae inhibitors, algae killers, etc. The pink bacteria was especially annoying and hard to get rid of without regular shocking. On top of that, tons of acid, alkalinity up, and calcium. Now all I mostly buy is a little acid and liquid chlorine from Lowes, Depot, or Warehouse Pool Supply and my pool looks better than any other time in it's 11-year history. I use a Liquidator which I installed with no drilling off a Tee from my old tablet chlorinator and my pump drain. I also added twenty mule team borax to 50 ppm borate levels. I keep my CYA at around 20-30ppm by adding a few tablets to the old chlorinator after a back flush. I also add a little calcium to keep levels above 250ppm.