quote:

Originally posted by Dandy Don:
So boys, what did I do wrong?
I have thought about the whole pump volume idea. But the fact that I can get a single stage with 20% methanol to pass the 3/27 with the same oil, same equipment and same solutions confuses me a little.
I can try it with NaOH and see what happens?
Any other ideas or suggestions?
Thanks,
DD

DD,

Your experience replicates my one-time experiment in doing the base-base process. I have an 80 gallon processor with the cheapy HF pump, and process a maximum of 50 gallons of oil at once. I tried the base-base process with 17% methanol. It took longer, was more labor intensive, and then it failed my 27/3 test. So I reached the conclusion that it wasn't worth the trouble to "save" 3% methanol, even if I could have gotten it to convert more completely.

In thinking about this, once the first reaction is finished and the glycerene is drained off, a lot of methonal would have been bound up with the glycerene and is now not available for stage 2.

Presumably what is left is a mixture of bio, a small amount of methonal, some left over catalyst and still some glycerene to be reacted.

Could being too skimpy with the second quantity of methonal required to react the residual glycerene lead to an incomplete conversion?

Because you are using less methanol in stage 1 it is more viscous and agitation becomes more critical. With some equipment it may not be a goer. Certainly if the conversion is not good enough it suggests agitation may not be adequate but the batch can be salvaged by doing a small stage 3.

OK, I'm ready to give this a try. Please check my math going by Chris da Pirate calculations

...
First Stage:140 ml methanol per litre of oil for the first stage and 4.2g NaOH (Adjusted for purity) plus titration times 1.15 in the first stage.
Second Stage: Use 0.8g NaOH (Adjusted for purity) in 23ml methanol.....

105 L of oil
NaOH and oil titration of .5

1st stage 14.7L meth
501.38g NaOH

2nd stage 2.4 L meth
84g NaOH

Thanks
Roger

Hello Rockytop

Are you using NaOH or KOH?
I recommend you use Neutral's Updated formula which is.

First Stage
140ml methanol
3.5g NaOH + (Titration X 1.15) or
4.9g KOH + (Titration X 1.15)

Second Stage
23ml Methanol
1.5g NaOH or
2.1g KOH

Adjust base amounts of NaOH/KOH for purity

Tilly,

Me thinks you are being silly

everyone knows that chemicle reactions in different parts of the world depends on the time zone and if you are in daylight saving time or not and if it is day or night when you mix the chemicles ! DA

BC

quote:

Originally posted by Tilly:
Hello Rockytop

Are you using NaOH or KOH?
I recommend you use Neutral's Updated formula which is.

First Stage
140ml methanol
3.5g NaOH + (Titration X 1.15) or
4.9g KOH + (Titration X 1.15)

Second Stage
23ml Methanol
1.5g NaOH or
2.1g KOH

Adjust base amounts of NaOH/KOH for purity

Thanks TILLY

I'm using NaOH 105L batch
Titrate = .5

1st stage 14.7L meth
427.9g NaOH

2nd stage 2.4L meth
157.5g NaOH

I'll give it a go tomorrow and report back. If it doesn't work I'll be walking as I am out of BD.

quote:

Originally posted by rockytop:

quote:

Originally posted by Tilly:
Hello Rockytop

Are you using NaOH or KOH?
I recommend you use Neutral's Updated formula which is.

First Stage
140ml methanol
3.5g NaOH + (Titration X 1.15) or
4.9g KOH + (Titration X 1.15)

Second Stage
23ml Methanol
1.5g NaOH or
2.1g KOH

Adjust base amounts of NaOH/KOH for purity

Thanks TILLY

I'm using NaOH 105L batch
Titrate = .5

1st stage 14.7L meth
427.9g NaOH

2nd stage 2.4L meth
157.5g NaOH

I'll give it a go tomorrow and report back. If it doesn't work I'll be walking as I am out of BD.

I'm very interested in knowing the results of your experience with NaOH.

Have a new happy and greasy year, for everybody.

(Excuse my english, my native language is spanish.. I try to do the best that I can...)

rockytop,

How did it work?

Did it pass 3/27?

What is your reactor?

Andrew

I tried a full 100L batch in a 40 gal appleseed this weekend using the updated formula except I used 30ml methanol in the second stage instead of 23ml. It seemed to pass the Warnqvest test just fine. My question is: What is the 1.15 in the (titration X 1.15) for? Is this simply to increase the amount of catalyst or are we adjusting for purity ?

quote:

I recommend you use Neutral's Updated formula which is.

First Stage
140ml methanol
3.5g NaOH + (Titration X 1.15) or
4.9g KOH + (Titration X 1.15)

Second Stage
23ml Methanol
1.5g NaOH or
2.1g KOH

Adjust base amounts of NaOH/KOH for purity

quote:

Originally posted by Andrew Morris:
rockytop,

How did it work?

Did it pass 3/27?

What is your reactor?

Andrew

Andrew sorry I never saw this post. I was off the internet a couple of weeks at this time and the thread got buried. I think you finally got my answers here:

http://biodiesel.infopop.cc/eve/forums/a/tpc/f/419605551/m/6931055381

It worked well. I got a 3/27 pass and using 40gal appleseed mixing with HF pump.

Roger

So I take it that the point of this it to try and reduce the amount of glycerol in the reactor, and try to maintain the excess of methanol to drive the reaction forward?

I wonder if you could continuously remove the glycerol somehow by passing the reaction mixture through a centrifuge, to achieve the same result?
Similar principle to a continuous distillation to remove a product from a reactor.

Hello Troy

If you were continuously removing the glycerine you would need to find a way to recover the methanol and NaOH from the glycerine because you would also be removing the chemicals along with the glycerine.

when it's in a well mixed reactor, surely the methanol would not be entirely bound up with the glycerol, otherwise I'd have thought the reaction would proceed too slowly. In a centrifuge I'm not sure the methanol and KOH would have time to migrate into the glycerol as happens in normal gravity settling.

It would be interesting to see. I'm sure some methanol and cat. would come out, but perhaps enough would remain to react? (possible continuous addition of catalyst/methanol?)

Hello troy
If you do a bit of a search on this subject you will find that it has been discussed and some university papers are refrenced etc...
Neutral also had some very clear thoughts about this.
Continuous addition of Catalyst/methanol is not a suitable answer as it would would result in using more methanol not less for the majority of homebrewers who are not recovering methanol.

Just for clarification, the university papers etc, were they in regard to continuous glycerol removal or continuous addition of methanol/catalyst?

Troy,

you may have have seen that recently I had a batch which was passed 3/27 using only 14.5% methanol.

I used 80/20 90/10 in my improved appleseed . With those ratios, the methanol in stage one is just below the stoychiometric amount used in the reaction. Frankly, I did not think it would pass 3/27. Apparently, stage 2 pushes it just enough farther to the right to achieve pretty high conversion.

Andrew

Thanks for that Tilly, certainly some interesting and in depth discussion about it. Given me some ideas, time to do some more research.

I'm hoping I am able to set up a continuous design process so for me it's not exactly relevant, but it's certainly interesting!

Andrew- Thankyou for that, it was something I was wondering about after reading some other threads about glycerol removal.