That looks good ff.
Does your glycerol go solid when using sodium methylate as the catalyst.
WOW, that looks significant!
Is that with using new VO as your feedstock?
What is sodium methylate exactly? Is it a solid that you still have to add to methanol or is it methanol and caustic premixed with the water removed, or perhaps non of the above?
I called my chemical supplier to get a price and they have never heard of it. Does it have any other common trade names that you know of? My supplier seems to only know stuff by the trade names, for example if call and ask for a bag of NaOH they say they have never heard of it but if I ask for a bag of caustic soda they have plenty.
Interesting, so it appears that it is a liquid consisting of 25% methanol.
How do you determine how much to use based on a titration?
Do you use it strait or mix it with more methanol?
Sorry for the 20 questions!
I read all about it on Duponts site but see no application instructions. It seems they make specifically for producing biodiesel. Curious stuff!
I sent Dupont an email asking about availability in Canada and it appears that Dupont has stopped making it all together.
And than this one came shortly after:
Looks like the dwindling biodiesel market took its toll on their SM business too...
The SM I get is 30% sodium. I use 2% SM base on oil volume and then add methanol to make a mix that is 20% of the oil volume. 100 gallons of oil, 2 gallons of SM and 18 gallons of methanol for example.
I don't know how to adjust for titration number because I use the no titration method. 2% is a good place to start and then you could adjust from there.
I suppose the way to know would be to make a titration solution with say 1 ml of SM per 1L of methanol and then titrate a 1 ml sample of the WVO in question the same as it is done traditionally with caustic...
Looks like the point is moot though as it appears that it is not sold here in Canada anyways...
Which no titration method are you using?
The no titration method I have tested is a two stage method but it makes no mention of using sodium methylate.
From your earlier post, you seem to be using a 2 stage No titration method that requires using the Warnqvest test to determine the amount of Caustic for the second stage. How do you adjust the caustic for the second stage after performing the Warnqvest test?
I am using the 80/20 no titration method. Any caustic used needs to be adjusted for oil quality.
I am using 2% SM based on oil volume on the first stage. So after doing a drop out test I calculate the "approximate" amount of oil in the batch and add 2% SM for that approximate volum to the second stage.
Dupont forwarded on my info, I got this email today:
So is 30% sodium what you would recommend? Or is it just what you have available?
If I am going to get a price I might as well ask for the best option...
I am assuming that you dont acid process since your oil is fresh. I wonder if when doing an acid stage if the SM would still increase yield?
Whey you mix NaOH or KOH with methanol, water is produced which then goes into the reactor and makes some soap from oil and biodiesel as a side reaction.
Sodium methylate does not contain water so there is less soap produced in the side reaction.
That is why using sodium methylate has a better yield than using KOH and methanol.
That would mean that you should get a better yield anytime you use Sodium methylate.
Hi fuelfrmer, in your above photo showing the increased yield, how much of an increase is that?
fuelfarmer; I'm interested in the sodium methylate in theory, but it is hard to get and dangerous. Anyway don't you make biodiesel primarily from new oil since you grow your own? My chemical supplier did things like talk to the state police on the phone when I ordered some anhydrous alcohol. Isn't using KOH with technical grade anhydrous (american) methanol good enough for most people. Sodium methylate is almost impossible to get for me in small quantities. My chemical supplier is paranoid, looking for the next Boston bomber. She thinks she's a national cop or something. One of my points is that using prepared anhydrous sodium methylate an unnecessary expense with small practical advantage?
Tilly, I don't know the yield increase without doing some checking. I will try to get the info. I am a farmer, not a good scientist. I have heard of as much as 8% increase.
WesleyB, I do use some used cooking oil that friends drop off as well as farm pressed oil. The farm pressed oil will titrate around 1.
SM is not any more dangerous than methanol or lye. Because it is liquid it is safer to handle and mix. No dust or over heating while mixing in methanol.
Mixing lye and methanol works just fine. But being a tinker has the curse of always looking for something better. I have not done the math but yield increase will cover most of the cost increase. And ease of use is a big plus.
Good graphic photo that illustrates one of the two main reasons for using a 2 stage Base/base method.
Reason number 1
You can get the same results as a single stage method using less chemicals.
(This is the reason I use a two stage method)
Reason number 2
If you use the same amount of chemicals, a 2 stage method gives higher conversion than a single stage.
(your photo demonstrates this reason)
The trade off in each instance is that a 2 stage method takes longer.
Growing in popularity over the last few years is:
Reason number 3
You have a reactor that is not capable of making biodiesel that passes Warnqvest in a single stage reaction. This problem seems to especially affect reactors based on small pump mixing.
Is there anyway to quantify that?
For example 25kg of Naoh mixed with 300L of 100% methanol will create X amount of water?
X amount of water will turn Y amount of oil into soap?
If so it shouldn't be to hard for me to figure out if its worthwhile or not, at least in theory.
I like the idea of having the caustic and methanol premixed and ready to go. Dumping 25kg of KOH into my methoxide mixer on a hot day is not fun...
FF, can you give me an idea of the cost of the SM? I assume you get it by the drum?
I just need to tidy up my previous statement a bit.
I will just talk about NaOH, but the same holds true with KOH.
When you mix NaOH with methanol, the chemical reaction that produces sodium methoxide (sodium methylate) also produces water.
CH3OH + NaOH --> CH3O-Na + H2O
However This is an equilibrium reaction in the same way that making biodiesel is an equilibrium reaction. Not all the Methanol and NaOH is converted into sodium methoxide.
The chemist Neutral always said that there was not really that much sodium methoxide produced, it was mainly just a mixture of NaOH and Methanol. If that is true then there is not that much water produced.
Some chemists say that most is sodium methoxide.
I have done some fairly extensive internet research over the years about just this point and I have never found the definitive answer. I think it depends in part on how much of each chemical is in the mix
The one thing that I do read over and over is that people who use the sodium methylate that FuelFarmer uses report higher yields using less chemicals than if you mix NaOH into methanol.
I would love to see some experimental results comparing the use of the two different sodium methoxide sources to see what the difference in yield and chemical usage is.
That is why I asked Fuel Farmer what his increase in yield was when he showed the photo and said he performed this exact test.
So the short answer is, I do not know how much water is produced or what the loss of yield would be.
OK, thanks for the detailed explanation!
I am going to see if I can get some SM, providing its cost effective to get it here.
If I do, I will report my results.
FF, is 30% sodium what you would recommend? I am wondering if getting a higher percentage would save on shipping costs...
Then I need to determine an accurate way to titrate with it. I dont see why it would be any different than how we titrate now with caustic other than the preparation.
I am thinking since its already in a methanol solution I should use 1L of methanol and add 1ml of SM to make the titration solution. Then to determine the base amount I guess I will have to experiment...
Anything wrong with that idea?
I will ask the supplier if they have collected any data from other producers also.
EDIT: I found this good thread about how to titrate with and use SM.
[QUOTE]Originally posted by fuelfarmer:
I did a single stage batch using the same amount of chemicals used in a two stage batch that passes the 90/10 drop out test.
Look at what I found with the single stage batch. More info soon.
In practice you are correct in what you say,however in thoery I think a single stage will go to completion with the same amount of chemicals, it just has to be left a lot longer.
There are some on the UK VOD forum that use 7.0 gms/litre KOH (and some even less than that) and get full conversion using single stage.
Their process time is 4 to 6 hours.
Don't get me wrong,ff the test you did was really good, Just saying.
I am not sure which theory you are talking about.
Every theory I have read supports the idea that a properly performed two stage method will give a higher conversion than a single stage method using the same amount of chemicals.
The graph that imakebiodiesel posted on the "Accelerated Conversion" thread shows this to be the case.
Just keep in mind that there is a wealth of inaccurate information posted to the internet about biodiesel production
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