I have a question that I am trying to get answered. Wondering if acid is worth it.

Here is a little history. I started doing single stages at first and have progressed to doing base/base (80/20 90/10). I feel that my yields are a little better than single and so is conversion.

Ingredients:
90L of wvo at 5-6 naoh average titration.
20% meth total (started at 22% and found 20% works due to testing)
Base catalyst is 6 naoh

1) process stage one for 2 hrs at 130F starting temp using 80% meth, 90% naoh. Temp climbs to 148F after mixing. Closed reactor.
2) drain glycerin after settling 1 hr.
3) process stage two for 2 hrs at 142F starting temp using 20% meth, 10% naoh. Temp climbs to 144 after mixing.
4) do 1L prewash for 15 min.
5) settle overnite and drain.
6) Wash 4-5 washes and dry.

My yield is 76L before wash and 65l after washing.
Bio passes 3/27 and has been tested also (thanks OU_Dave).

Will acid get my yields up to say above 90% vs my current yield vs time involved and material costs? Would it be worth doing a base/base on the acid or just a single stage after acid?
Do you use the base naoh plus titration for acid processing as for "standard" processing?

Just seeing what is best method in other peoples eyes vs time & money.

Thanks

This message has been edited. Last edited by: duramadmax,

With two stage processing you should be able to get full conversion with less than 6 grams base. I use something closer to 4. Extra lye speeds up the conversion but produces more soap.

As far as yield goes, you should definitely be able to get past 90% if you run an acid stage first. You can also split your byproduct and put the FFA's back into the next batch.

--- David

anything under titration of 8 KOH and I use glycerine pretreat. Over that I use acid. Yields are between 80-85 percent with pretreat, and 90-97 percent with acid. I get my 93 percent pure acid for 7.00/gallon, so the cost is not a factor. Time is

thanks for the comments so far. My glycerin is solid after draining and cooling but pretreat would be a good method if my glycerin was liquid. As most of my summer oil is PHO and winter is Soy

On cracking the glycerin back into ffa's and such, what is the formula you guys use?

I throw 10 gallons or so of glycerine(not dememthed yet) into 50 gallons of oil. Heat to 130, mix for 2 hours, and settle for 12-24 hrs.
Drain off, heat back to temp, titrate and process.
For acid base, see the thread at the top by DKenny

Oh, and for liquid glycerine, switch to KOH or reheat your Naoh glycerine.