Hello
My WVO typically titrates at 9. I want to try an acid treatment on it with sulfuric acid. Is there any step by step instructions (think acid esterification for dummies) that someone can share with me?
Thanks

sure it easy

titration - 3 = 6 in your case
6 * 0.2 = 1.2 ml/Liter -> this is the amount of sulfuric acid you need to use

use 12% of the oil volume for the methanol volume.
a 100 gallons of oil would use 12 gallons of methanol

heat the oil to 140F. make sure the oil is dry.

pour the acid into the methanol slowly. IT WILL BOIL violently.

add the acid/methanol mix to the heated oil.

mix for 10-12 hours. if you like check the titration every hour. if it gets to 3 or less before 10 hours its done.

proceed with the base part of the process. use 8% of the oil volume for the methanol volume. this make a total of 20% for the methanol.

handle the sulfuric acid with great care..

-dkenny

What purity of sulfuric acid?

It is rated at 95-98%

Thanks

that would just fine.

-dkenny

A little confused since the homebrew recipes in the stickied thread show different values for sulfuric acid.

It is really this simple? I have never done acid-base before but really eager to learn so any feedback using this method will be very much appreciated.

superfunkibey,
yes it used to hard and confusing..
I got put between a rock and hard place..ie lots of high titrating oil..so i figured out an easier way. but it is based on the other methods.
and to date I have only messed up 1 batch. something else was causing a high titration reading besides FFA's..so my titration went up not down.

-dkenny

Can acid-base method be used to process lard or beef tallow? How about solid animal fats?

dkenny:

I'd like to know what was causing the high titration in your sole failed batch?

dkenny I believe from sample test that I have done, that oil that contains the grill cleaner and other degreasers causes that rise in titration. ask your suppliers if the are dumping that in the oil tank It still makes good fuel for the turk burner.

Hello superfunkibey
Animal fats are no different to react than veggie oil.
Do a titration and if the titration is not too high just do a normal single stage method.
Over the years I have processed lots of animal fat using the single stage method.
Just make sure everthing is liquid during the reaction.

Many thanks Tilly and dkenny for your help.

One last thing though. If ever I would do acid pretreatment, would regular 16 gauge stainless steel tank and plumbing be up to the task?

I would think so. mine is a water heater with black iron pipe.

-dkenny

quote:

Originally posted by superfunkibey:
Many thanks Tilly and dkenny for your help.

One last thing though. If ever I would do acid pretreatment, would regular 16 gauge stainless steel tank and plumbing be up to the task?

The strong acid needed will react with the metal. It would be best if you could find a glass lined tank. It could be a lot smaller than your regular reactor. Then just make a series of acid stage batches until you have enough to do the base reaction in the main reactor. Separate containers for each process avoids conflicting contaminations. Goodluck

Hello all,
I would just like to add, I have used this method on two batches so far and it has worked well for me. Longer wash than I expected, but the results and yeilds are good. My second batch started out titrating at 12ml NaOH. After using dkenny's method, it pushed the titration down to 3ml in about 12 hours. At that point I processed normally, the batch is washing now. Expect to have fresh bd by Monday!! Thank you dkenny. This is definitely something to consider if all you can get your hands on is high FFA stock. Just a note, be sure to have adequate ventilation, especially when adding the acid to the methanol. I add it very slowly, gently to half of what I intend to use. After adding the acid, I pump in the rest of my meth to my premix container. Then inject slowly to get good dispertion throughout the volume of the batch. Remember, safety first. Good mixing!!!

Concerning the question of whether or not you can do it in a 55 gal. metal barrel. I have been told that if you have an Appleseed processor, you can do the acid esterification in the water heater and when it is done, just proceed to the regular process.

As for the regular process, can someone tell me how to calculate how much KOH to add to the methanol for a batch? I am getting ready to make my first batch. Also, what is the maximum amount of biodiesel you can put in a standpipe wash system using a 55 gallon drum. Thanks.

patcherman,
if by the regular process you mean the base stage part. just think of this as a single stage base..

so its base + titration for the caustic.

I have no idea on the standpipe..sorry

-dkenny