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Theoretical pH of manufactured product

  1. Apr 4, 2012 #1
    Need urgent help with a manufacturing problem.

    Our company built a product that is testing in spec for propionic acid and ammonia, but out of spec for pH. Desperate for this answer.

    The total product build is 24166.246 KG.

    The amount of propionic acid added is 15949.723 KG, which puts us at 66% prop by formulation. GC testing gave 66.4%

    The ammonia source is anhydrous ammonia that is supposed to be delivered at 1329.144 KG for 5.5% in the build via kjeldahl distillation and titration. Testing gave us 5.35.

    Prop is in spec but on the high end, ammonia is in spec on the low end, and pH is just out of spec high. I cannot add any prop acid in without risking kicking it out of spec.

    I NEED to know... what is the theoretical pH of the above build... with 66.4% prop acid (assume 100% even though is 99.5%+) with 5.35% ammonia?

    Thanks so much in advance.

    This isn't about grades for me. I'm trying to help a plant that has had big problems keep open. That means paychecks.

    If you can't help me, please kick me in the right direction?

    I've got about 16 hours to figure this out before all heck breaks loose.

    Feel free to call me Drama Queen.
  2. jcsd
  3. Apr 5, 2012 #2


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    Staff: Mentor

    If I understand what you wrote correctly, your mixture contains just about 40% of water? If so, what you have is a concentrated soup with a very high ionic strength, I doubt anyone would be able to calculate reliable value of pH. I would expect something between 4 and 5.
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