I am finally having some success in repeating the biodiesel process. The oil I am getting is pretty high titration, around 10mL. Add the base amount for KOH and I get 14.9mL/Liter oil. This was killing me for having to make such a strong methoxide and the yield was horrible (75%). I actually started making a two-step process, yielding soap in the first and biodiesel in the second. I have been adding the titration amount of KOH to 40mL of distilled water and gently mixing until uniform. The soap settles out overnight and pulls the water with it. I siphon off the oil and run as virgin oil and after one hour mix at 130F and one hour settle time I have biodiesel. The separation in this second stage is very quick and the yield is almost perfect in volume. I am filing for my business license this week to buy from a local chemical supplier and should finally be up and running next week.

I remember Fabman saying that a different two-stage method did not work. Is this method listed on a community access page? I am told by a chemist that an acid-base two-stage method could work. The yield would increase along with the cost involved, but the waste from the process would go down. Any input from the trenches?

Thanks, Ben

 

There are a couple of two stage systems that I know of the base-base method you described and the acid base method.

here are URLs for how-to on both methods:

Base-Base
http://journeytoforever.org/biodiesel_aleks.html

Acid-Base
http://journeytoforever.org/biodiesel_aleksnew.html

If you look at the base-base method you will find that you left some things out at the end of the process, assuming your description was complete.

 

Thanks, Phydeaux88,

I gave the abridged version in my last post. I have been through the JTF website and could spend weeks reading (driving my wife up a wall in the process). I also have seen both of these methods described in a paper from Iowa State University. Long, but full of pertinent information. I looking for someone to who has experience with the acid-base method. I am curious about any suitable drop in replacements for sulphuric acid. Any ideas?

Thanks, Ben

 

According to what I have read it is important that the sulphate ion (SO4)be involved so there is no sub for sulphuric acid. I suspect it has somthing to do with its affinity for sodium in the base stage. Na2(SO4), sodium sulphate, is very soluble in water and thus is easily removed in the wash.

 

I have looked more closely at the reaction, but admit my knowledge of chemistry stops at high school level, so far. I do believe I have found a decent source of H2SO4 with Lab Safety. Others want more money than I am willing to give and/or restrict quantities to more than I will use in five years. Too bad HCl won't work. I could sell the yielded salt in cakes for deer licks in Michigan. Oh, well...

Thanks,

Ben