Neutral, does this mean a 5 seconds shake is enough?

While reading Smokeys referance at this site I found this:

"A high degree of conversion could be obtained only if the oil and alcohol phases have been blended into one homogeneous phase. This requires extremely vigorous agitation with some splashing at the start of the reaction. When the reaction mixture is homogeneous, the conversion and time to reach maximum conversion are independent of agitation."

Tilly SBC/IBA No longer great oricle of wisdom

Never lick a gift horse in the mouth.

Tilly,

I read somewhere that a spy sat' over Aus detected a very large grin. Could this be related to this ?

I believe it was the great Tilly, our Worshipfull Master, who told me about six months ago, when I had just started experimenting with BD, that the mixing only needs to be done quickly for a very short time, and up till now, He has been proved always right!

H.C. At The Grovelling In The Dirt Div. SWC

It looks like Dr Pepper stocks are about to soar!!

HC, for being so good at grovelling, when I become king of Biodiesel, I will find some meaningless, but rediculously highly paid job for you.

Tilly SBC/IBA Soon to be the oracle of biodiesel

A day without fusion is like a day without sunshine.

Tilly

The article you referred certainly endorses your assertion that vigorous agitation is needed to get the reaction started.

The paper states that the reaction was tested at 30, 60 and 120 minutes. Unfortunately it does not state what levels of conversion were achieved over these times.

It does however state that higher temperature reduced the time needed to obtain maximum conversion. It appears therefore that some time is needed to obtain maximum conversion.

Clearly they have shown that once the material is fully agitated the level of agitation is no longer important. But the question of how long gentle agitation, or occasional shaking, should be continued after the initial severe agitation is not answered in this paper.

It is pretty interesting that they have fully endorsed BioCruiser's method of washing, saying it minimizes emulsion formation.

Yes, I have NEVER said that the conversion is instentanious. Indeed, I have often pointed out that warm oil takes about an hour to reach completion, and conversley,I have pointed out that COLD oil may take many hours to reach completion.

I know you have said this was what your tests showed and so does, it apperars, the Idaho tests show that the colder the oil the longer the reaction takes to reach completion. This is also what my tests show.

I think the significant part of their test conclusion is:
"When the reaction mixture is homogeneous, the conversion and time to reach maximum conversion are independent of agitation."
This certainly says to me than once an homogeneous mixture is reached (after 5 seconds?), you can mix any way you like because it will make NO difference to the final quality of the biodiesel.

Yes, I knew 'Cruiser was not the first one to recommend spray washing. I had forgotten where I had seen it before, until Smokey pointed it out last night.

Tilly SBC/IBA 5 second devision.

You can't buy happiness but you can lease it.

Tilly

When you say "mix any way you like" does that include not mixing at all?

Tilly SBC/IBA

Never try to guess your wife's size. Just buy her anything marked "petite" and hold on to the receipt.

Tilly SBC/IBA
Never try to guess your wife's size. Just buy her anything marked "petite" and hold on to the receipt
..........
once again, you prove your worth, oh great one!

I go one step further down the trail of Married Man's Wisdom...I just buy Her Ladyship a Gift Voucher...saves on time etc, as whatever I do...its always the wrong size/style/colour/etc etc ad infinitum...

Actually, BioCruiser only perfected the spray-mist 'cos I used to tell him that "bubbles" was the ONLY way to go...'Ornery old coot just could'nt resist the challenge !!!

Anyway, I still have great success with (gentle...) bubbles, using the Uni of Idaho (non-patented..) method of re-mixing/washing...but it goes even faster if I start with a 20 litre spray-wash first... That way, I get the best of both approaches

Cheers, James From Perth.

Can you get a homogeneous mixture of oil and Methoxide ?
No mater how hard I mix I can only get a polar suspension and if the oil is too cold and only agitated at the start I will get a lot of straight methoxide floating on top of the mixture before it has been used in the reaction.
Ethoxide does form a homogeneous mix I am told.
John

Good question JohnO

Certainly when you mix the oil with the methanol/NaOH the solubility of the methanol in the oil is exceeded, so there are initially two phases.

It is also obviously true that when the reaction is complete there are two phases. In both these cases clearly the material is not homogenious.

The question is, what happens in between. The in-between phase doesn't last long with severe agitation, and is pretty inscrutable. With clean oil an orange colour can be briefly seen. As none of the ingredients or products are orange this must be a short-lived intermediate.

Finely divided it can be, but whether homogenious I do not know. I would dodge the issue and avoid using the word in a paper without further evidence.

I took the "Liberty" to email Chuck Peterson, the head of the Idaho University biodiesel project, and briefly described some of my tests and their outcomes. I then asked him about mixing times for biodiesel, and this was his reply:

"It is generally understood that the required mixing time is very
short. However, to be certain that we meet the ASTM PS-121
spec. on glycerol content we generally mix a lot longer to
assure full conversion. Commercial operations often do a second
treatment with alcohol and catalyst to assure full conversion.

Chuck Peterson"

Tilly SBC/IBA 10 second devision

Arachibutyrophobia: fear of peanut butter sticking to roof of mouth.

[This message was edited by Tilly on 01 April 2002 at 10:14 PM.]

Looks like a neat side step to me. Where is his graph?

Now it's your turn to send an email.

As you are a chemist, you will know what to ask.

Tilly SBC/IBA 10 sec or 1 hour div

E Pluribus Modem

into google and you will come up with the email.

Tilly SBC/IBA Paradise idv

Shin: a device for finding furniture in the dark.

How is your Gemini going? and a question, Do you wash, or is that a personal question!

H.C. At Enquiring Minds want to know Div. SWC.

The Gemini is going fine.
The only problem I have is that although the car starts right up in the morning when it is cold, when it is just partly warmed up the timing circuit cut the glow plugs back to just a brief glow.

If I do not turn the switch off and on several times, it takes a lot of cranking to get it started.

When it is thoroughly warmed up, I have no problems.

I will have to put in a momentary on switch for the glow plug circuit like my old diesel utes had.

Yes, I wash myself and my diesel. I use biocruisers mist wash technique.

Tilly SBC/IBA

Federal Express is a fly-by-night company