My glycerin is KOH reacted. What acid and how much to neutralize it. I've looked all over the site and have not found an answer.

Why do you believe you have to neutralize the glycerol?

Not sure. When searching this site, I noticed a lot of discussion about neutralization. How do I check my glycerin to determine if I need to or not?

I duuno if "neutralize" is the right word to use, unless the idea is to bring the PH to 7, which is neutral.

As is the glycerin layer is partly saponified, meaning that it is mostly soap, along with methanol and perhaps a couple other contaminants depending on how it was processed.

If you remove/distill off the methanol and add 40gr KOH per liter of glycerine dissolved into a liter of water to the glycerine you have liquid soap that has any number of practical applications.The PH should range between 9 and 10.5 or slightly alkaline.

As is, it will probably be close to neutral or ever so slightly alkaline and a little acid (take your pick) could bring it back to neutral. Of course the question begs: why do you want it neutral?

Now if making a bunch of soap isn't your thing then you can still remove the methanol and use it as is for either a degreaser or as an additive with mulch for gardening, or animal feed, ruminants in particular.

If you can give a clearer perspective on what you want to do then it will be easier to give a more concrete answer.

You can check your glycerin the same way you would check biodiesel for soap. Or use a pH probe if you want true (7) neutral.

It also depends on why you want to neutralize? Do you want to take the pH down to 7 or do you want to completely break the soaps back into FFA to split the crude glycerin. When I do this my glycerin normally ends up at a pH of 6 or so, slightly on the acidic side.

How much acid you need is going to vary depending on the initial titration and water content of your oil, this is why you won't find much concrete answers with regards to exactly how much you need.

L.E., I bought your soap guide awhile back. I should reread it, huh? What I am trying to achieve is to get the glycerin to a more pure level, sort of a technical grade. Don't know if that is possible, but you know us biodiesel guys, always trying something.

I hope this is the right place to post this. The topic responses did not answer my question. I used phosphoric acid to get purer glycerin and separate out FFAs and catalyst KOH, what do I use to neutralize the phosphoric acid and how much?