whattabrau
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Literature says HCl is dangerous, but I haven't found anything written in terms of practical handling for a homebrewer (with apologies if such material does exist). background: I have high-alkalinity tap water which is single-digit mg/L except for Ca and CO3. I'm tired of removing the temporary alkality for pale brews for various reasons (time, lack of a large enough container, effort, cost, etc), so at least in some cases I want to try hydrochloric acid in the mix for neutralizing the alkalinity.
The options I've found for E507 are 4%, 10% and 37%, with the price for 1L being roughly the same. Is there any real difference between the danger of any of those, or am I just buying expensive water with anything except the 37%? I'm planning to store the container away from metals in an outdoor shed, which is not exactly airtight, but I do spend lengthy periods of time in there occasionally. I'm planning to put on gloves and goggles and prepare a dilute solution (<<1%) first thing on brewday, which at least in my mind puts me out of the danger zone for the rest of the brewday. If my calculations are correct, a volume of 10% HCl is enough to treat 1000-2000x water before the chloride levels get too high for most beers, making it pennies per liter, which I'd start finding acceptable if there is a safety benefit over the sub-penny liter cost of 37%.
I don't know where to get AMS locally; it seems to be about the equivalent strength of 10% HCl, and the lack of any excessive safety warnings on or around AMS discussions is making me think 10% HCl is not *too* dangerous. Though I'm not sure if the included sulfuric acid is making AMS less dangerous as compared to pure HCl (= reducing HCl off-gassing).
Finally, is HCl really all that much more dangerous than the 80% lactic and 75% phosphoric acids that I already use?
Bonus question (chemistry): does the order in which the acids are added in matter? I'm guessing yes, at least in theory for phosphoric acid where the second pKa is a hair above 7, i.e. if added first you get at least some of the phosphoric acid to protonate twice and bubble some of the CO3 out as CO2. Correct, or "that's not how chemistry works", or correct but [ignoring apatite] the effect is negligible in reality? If nobody knows, I guess I can figure this out with a pH meter once I have the HCl, and from the experimental result work back towards the chemistry.
The options I've found for E507 are 4%, 10% and 37%, with the price for 1L being roughly the same. Is there any real difference between the danger of any of those, or am I just buying expensive water with anything except the 37%? I'm planning to store the container away from metals in an outdoor shed, which is not exactly airtight, but I do spend lengthy periods of time in there occasionally. I'm planning to put on gloves and goggles and prepare a dilute solution (<<1%) first thing on brewday, which at least in my mind puts me out of the danger zone for the rest of the brewday. If my calculations are correct, a volume of 10% HCl is enough to treat 1000-2000x water before the chloride levels get too high for most beers, making it pennies per liter, which I'd start finding acceptable if there is a safety benefit over the sub-penny liter cost of 37%.
I don't know where to get AMS locally; it seems to be about the equivalent strength of 10% HCl, and the lack of any excessive safety warnings on or around AMS discussions is making me think 10% HCl is not *too* dangerous. Though I'm not sure if the included sulfuric acid is making AMS less dangerous as compared to pure HCl (= reducing HCl off-gassing).
Finally, is HCl really all that much more dangerous than the 80% lactic and 75% phosphoric acids that I already use?
Bonus question (chemistry): does the order in which the acids are added in matter? I'm guessing yes, at least in theory for phosphoric acid where the second pKa is a hair above 7, i.e. if added first you get at least some of the phosphoric acid to protonate twice and bubble some of the CO3 out as CO2. Correct, or "that's not how chemistry works", or correct but [ignoring apatite] the effect is negligible in reality? If nobody knows, I guess I can figure this out with a pH meter once I have the HCl, and from the experimental result work back towards the chemistry.