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All Roof Cleaning Lake Charles Louisiana wrote:

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My wife, MS Degree in Chemisty, and 25 plus years in Chloro-Alkali industry say, "I don't think so."

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Thanks Dennis.  If the Mrs. is willing, and only if she is willing, could you kindly ask her to explain in lay terms?  I don't doubt her answer one bit, yet based on my recently new profession, I'd REALLY like to better understand this and be able to speak to this.

The big household manufactures put it in there for something I would think.

I stunk at chemistry.  Balancing chemical equations KILLED my GPA.

*White flag emoticon goes here*

Thanks bud, and many thanks to your wife.

All Roof Cleaning Lake Charles Louisiana wrote:

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First a quick lesson in how chlorine and sodium hydroxide are made.

Chlorine and NaOH (commonly called caustic soda) are products of the electrolysis of NaCl (table salt). One other product from this reaction is hydrogen gas. There are three major chloro-alkali producers in the US. Some also make sodium hypochlorite, however a lot of SH is produced by smaller companies that purchase chlorine and caustic from the big guys and make the SH themselves.

Sodium Hypochloite can be made by reintroducing chlorine into a solution of sodium hydroxide (simply mix the two back together) or it can be pulled off as a side stream during the process of making chlorine and sodium hydroxide in the electrolysis process.

On your question about, "The big household manufactures put it in there for something I would think."?..... Chris Tucker is absolutely right (no surprise) in his answer that they put extra sodium hydroxide in. The slight excess is there to retain as much of the free chlorine as it can... to give it a longer shelf life. There is only so much that can be done to retain the chlorine... the longer SH sets and the hotter the storage temperature, those chlorine molecules are getting there act together and finding a way out of solution. It may stand to reason that putting in more sodium hydroxide could hold it in longer, but there's more to the chemistry than just dilution and adsorption.

Hope this helps.

Dennis

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