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-7deg C Biodiesel Reaction
Hi Everyone,
There has been some discussion lately about making biodiesel at ambient temperature- without heating.
Many years ago I did a number of experiments to sort out the truth from the well meaning nonsense that was posted concerning whether it is required to heat the reaction.
One of the experiments I performed was to do the reaction at 4deg C which did make biodiesel
As it is raining this morning, I decided to have another look at low temperature reactions.
I took a litre of my current production WVO, poured it in a 2 litre Dr Pepper bottle and placed it in a freezer with a thermometer in the WVO.
I made the required methoxide by mixing 9g KOH into 140ml methanol in a coffee cup, stirred until the KOH was dissolved and then placed the coffee cup in the freezer with a thermometer.
I kept checking back and to my very great surprise the WVO was still liquid at -7C. At this point I decided that was cold enough. The methoxide had already dropped passed -7C so I allowed the methoxide to warm back up to -7C, added it to the bottle of WVO, screwed the top down tight and shook hard for around 30 seconds.
The contents of the bottle went white and thickened.
At the time I thought it was probably a failure but I did notice that while the sides of the Dr Pepper bottle initially contracted with the shaking, the sides did start to fill back out which suggested there was a reaction going on.
So I set the bottle back in the freezer and when I checked back a few minutes later the contents of the bottle had changed colour back to an oil colour.
Of course, it had gone through the initial main part of the reaction where the viscosity increases and then reduces. However at this low temperature, instead of taking 10- 15 seconds to do it took several minutes
Over the next five minutes or so, I left the Dr Pepper bottle in the freezer and I came back several times and re-shook the bottle.
I then removed the top of the bottle and there was a release of pressure. Then I put a thermometer in the bottle and noted the temperature had increased to around -4C. These were both sure signs that the reaction was occurring.
I then let the bottle sit in the freezer for a few hours, making sure the Temperature stayed around -7C.
I now have a Dr Pepper bottle with biodiesel sitting on top a layer of by-product- all at -7 deg C
Hi Everyone,
There has been some discussion lately about making biodiesel at ambient temperature- without heating.
Many years ago I did a number of experiments to sort out the truth from the well meaning nonsense that was posted concerning whether it is required to heat the reaction.
One of the experiments I performed was to do the reaction at 4deg C which did make biodiesel
As it is raining this morning, I decided to have another look at low temperature reactions.
I took a litre of my current production WVO, poured it in a 2 litre Dr Pepper bottle and placed it in a freezer with a thermometer in the WVO.
I made the required methoxide by mixing 9g KOH into 140ml methanol in a coffee cup, stirred until the KOH was dissolved and then placed the coffee cup in the freezer with a thermometer.
I kept checking back and to my very great surprise the WVO was still liquid at -7C. At this point I decided that was cold enough. The methoxide had already dropped passed -7C so I allowed the methoxide to warm back up to -7C, added it to the bottle of WVO, screwed the top down tight and shook hard for around 30 seconds.
The contents of the bottle went white and thickened.
At the time I thought it was probably a failure but I did notice that while the sides of the Dr Pepper bottle initially contracted with the shaking, the sides did start to fill back out which suggested there was a reaction going on.
So I set the bottle back in the freezer and when I checked back a few minutes later the contents of the bottle had changed colour back to an oil colour.
Of course, it had gone through the initial main part of the reaction where the viscosity increases and then reduces. However at this low temperature, instead of taking 10- 15 seconds to do it took several minutes
Over the next five minutes or so, I left the Dr Pepper bottle in the freezer and I came back several times and re-shook the bottle.
I then removed the top of the bottle and there was a release of pressure. Then I put a thermometer in the bottle and noted the temperature had increased to around -4C. These were both sure signs that the reaction was occurring.
I then let the bottle sit in the freezer for a few hours, making sure the Temperature stayed around -7C.
I now have a Dr Pepper bottle with biodiesel sitting on top a layer of by-product- all at -7 deg C
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