Mixing types of acids for pickle

Submitted by mrdux on 5/8/05 at 8:45 AM. ( mrdux@refugemail.com ) 67.32.171.108

I have checked the archives and may not have entered the correct words to get answers to my question. I am currently pickling an elk cape in formic acid pickle solution. I bought a quart to try it and have found that I'm almost out of formic and I haven't shaved the cape. My pickle solution is not clean but I think it will be OK for using after shaving. My question; can different types of acids be used in one pickle solution? I have used Safety acid in other pickles and have over a gallon of it on hand. I had to mix up a 10 gallon formic pickle and may not have enough formic left to adjust the ph down if it goes up very much.I started at a 1.5 ph but it has crept up to around 2 and I have added formic twice to get it back to 1.5. Can I safely add a small amount of Safety acid to a formic pickle? I worked in the chemical industry for 27 years and dealt with lots of very dangerous acids(nitric, sulfuric,etc) and understand the dangers of acids splashes, boil,fumes,etc. I just don't want to ruin a beautiful cape! Any assistance will be most appreciated.

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Don't worry so much

This response submitted by Dean on 5/8/05 at 11:33 AM. ( ) 63.26.114.28

As long as it is under 3.0 you will be okay. Did you use a bacteriacide in the solution? Ph level of 2.0 to 2.5 is the magic numbers I was told that you want. I think 1.5 is almost getting to low. I've never run it at that level. Maybe someone from a tannery can say more about it.


Low PH

This response submitted by John on 5/8/05 at 11:54 AM. ( ) 68.206.87.230

I don't worry about too low PH. Mine is usually around 1.5 to 2.0. I do use saftee acid though.


You're too low using Formic!

This response submitted by Bruce Rittel on 5/8/05 at 3:31 PM. ( rittel@mindspring.com ) 207.69.136.197

Formic "bottoms" out at around 2.0-2.2. No matter how much you use - you'll never go lower. So dont waste your acid and settle for a PH level of 2.0-2.2 and you'll be fine. This is the typical range for a Formic Acid pickle. You may be OK as is and not have to add another acid.

Using Saftee Acid with it will bring it lower - but you will have to use an excess amount of it. Not 0.5 fl. ozs. per 1 gallon. Maybe more like 4 fl. ozs. per 1 gallon of pickle - it all depends on how much excess Formic Acid is already in the pickle.


Just did this in the lab...

This response submitted by cyclone on 5/9/05 at 12:18 PM. ( ) 129.43.43.200

Formic can and will drop below a pH of 2. Mixing equal amounts of formic (88%) and distilled water, creats a 44% solution and it will pH below 1. I'm guessing that the pH paper most of you all are using bottoms out at 2...

and/or the water used for the pickles contains minerals, scale or has been "softened"..This will cause a "buffering" effect and will take more acid to lower the pH.


As for mixing acids

This response submitted by cyclone on 5/9/05 at 12:25 PM. ( ) 129.43.43.200

I wouldn't...

for instance

alone concentrated hydrochloric acid won't touch gold
nor will concentrated nitric acid...

but, mix 3 parts hydrochloric and 1 part nitric acid (Aqua regia) and it will dissolve gold.....


Thanks for responses

This response submitted by mrdux on 5/9/05 at 8:30 PM. ( ) 67.32.171.108

I appreciate all input on my question. I shaved the elk cape today and put it back into the pickle for a couple more days.As for shaving, I didn't notice any difference with the formic pickle as opposed to my normal Safety acid. There was the vinegar smell that isn't there with Safety. I do know that the formic recipe I used is MUCH more expensive.

BTW, I use 0-3 ph paper and just opened a new package. My pickle has read as low as 1.5 and is currently reading between 1.5 and 2.0 with the formic pickle.


Mr. Smith

This response submitted by poop face on 5/17/05 at 8:16 AM. ( ) 169.244.70.148

u suck

tell u r mom i had fun last night


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