I've made bio in the past but not for quite some time. My first batch in a while didn't pass the water test. So I either didn't titrate correctly and used to much or to little HaOH or got an incomplete reaction? I found a bio calcutator on line. It states 2 different amounts of NaOH 5 gr. as a base plus your titration if you are washing and 3.5 gr plus your titration if you aren't washing? Is this right? I used the higher amount for I am washing my fuel. So if I used to much NaOH and created lots of soap, is it a lost batch? What is my next step? Re-process? Throw it out and start over? Help Please

Dave

P.S. There is also a thin layer/film on top of the fuel? What does this mean?

Thanks for any help!

Dave

I use 5 as a base and I wash my fuel. I would not use unwashed fuel. I tried 3.5 as a base and could not pass a 3/27 test after the first reaction.

The film is likely a thin layer of soap. I have had this and I scooped it off with a kitchen strainer prior to washing.

With the higher base you may produce a little more soap, but you will also make more highly converted BD. The soap can be washed out, but unreacted triglycerides and diglycerides can not.