So I use glacial acetic acid to pickle hot rolled steel to remove mill scale. When I first mixed it up I did 25%. Since then I have guessed at adding water and more acid leaving me at no clue as to the strength. Do I want PH test strips ? Am I over thinking this as in the stronger the better ? I'm sure someone here can send me in the right direction. Thanks for any help Keith
Well, I just read this. I’m trying to figure out exactly what you’re looking for. Is there an ideal pH that you are trying to achieve? Or do you just want to know how much the change in concentration affects the pH? Interesting problem.. Glacial Acetic Acid Versus Ordinary Acetic Acid there are sites that walk you through the calculations…. I’d probably need a scotch to lube the neurons before attempting thisss.. How do you calculate the pH of acetic acid? + Example
When I first did 25% it worked fine and did the job. But with evaporation and I'm sure weakening the acid plus me adding acid it's now unknown what it is. I was hoping to make a accurate 25% mix and use it as a "standard" of comparison. But I'm not sure what to get for use in comparing the two. Also it's contaminated with mill scale if that matters. If I can get 25% strength +- say 5% I think that would work.
So I think you might be able to determine the concentration if you had a hydrometer similar to what they use to determine the sugar concentration in maple sap. This website talks about how to calculate the density based on the mixture of concentrated acetic acid vs water. If you know what your density is to start off with, you can add acid or water to get back to that density. More than one way to skin a cat. https://www.quora.com/Suppose-a-sol...ter-What-pH-will-the-solution-have-at?share=1
Looks like a home brewing hydrometer might work for the measurement scale you are working with. Hydrometer Scales and What They Mean
I wonder if the one for a lead acid battery would work. I have those I'll give it a try can't hurt. Thank you for your time and help it's much appreciated!!
No. I actually took the time to read it.. if I was in school, I’d be staring at the legs of the hot girl sitting next to me and would have learned nothing while sitting in class… so if concentrated acetic acid has a specific gravity of 1.049 and water is 1, then your 25% solution should be 1.01225…. If your specific gravity ends up at 1.00612, you are now at a 12% solution and would have to add an amount of acetic acid equal to about 17% of the total mass to get back to 25%…. So say you start with 100 kg of solution of which 25 kg is acetic acid.. at the end of the process, you still have 100 kg of solution (some insoluble iron compound will have precipitated out) with 12 kg of acetic acid…. So if you add 17kg, you are now at 117 kg of solution with 29 kg (or 25% being acetic acid…. Measure with the hydrometer, math with a calculator..,
We've pickled SS pipe and cleaned up SS welds but always used the acid straight out of the jug. I know. I'm not much help. Just moral support.
How about using a refractometer? Way quicker than other methods. I use one for determining the specific gravity of my saltwater reef aquarium. Here's an article. Read a bit down past all of the jargon. A New Approach – Concentration Measurement of Bases and Acids using a Refractometer A refractometer is under $20.