Re: Eau de Javelle ( Javel )
Christina wrote: My question is this: what percentage is Chlorox Bleach or common household bleach today, so if we wanted to make a current day Javelle water by adding a bit of sodium carbonate to bleach (Arm and Hammer Washing Soda is sodium carbonate) I wonder what the dilution is. Thanks, Dan, for finding the percentage bleach of 6%. So if one mixed a little washing soda into the bleach it should approximate Javelle. I am shocked to find out Chlorox is only 6% because I can't imagine soaking a print in straight Chlorox!!! Gives me the heebeejeebees, too.Hypochlorite in solution is kept at least slightly alkaline to prevent the release of chlorine gas. Household bleach is generally made alkaline by hydroxide (a byproduct of the industrial process by which the hypochlorite is produced) rather than carbonate. Assuming that the alkalinity is the reason for the carbonate in Javel water, household bleach at the appropriate dilution should be a fine substitute as it is. You may want to play with the dilution, depending on the process. If you wanted to reduce the alkalinity, you could add small amounts of hydrochloric acid while monitoring the pH (you would NOT want to go so far as to make the solution acidic). Photographic hypo (sodium thiosulfate) decomposes hypochlorite and could serve as a wash aid. (If you were not using the hypo as a silver fixer -- i.e., to dissolve remaining silver halides -- you would not form the complexes that are so hard to wash out after a thiosulfate fixing bath.) Finally, to avoid releasing chlorine gas, do not mix household bleach with an acid. Lime and scale removers, which often contain a metabisulfite, and acidic drain cleaners (generally sulfuric acid), will liberate chlorine gas from household bleach, as many people have found quite by accident. (I seem to recall that Dick Sullivan had a tale of generating a cloud of chlorine gas while trying to clear a plugged drain.) Best regards, etienne
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