Thought i'd post a quick tutorial/guide/example of how i am trying to make biodiesel from veg oil.
I'm doing this purely as a proof of principle exercise. If i can produce a small quantity of a rough product using nothing more than some chemicals then i figure scaling it up with proper equipment shouldnt be too difficult, and then move to WVO.
I'm a professional research scientist who works with hazardous chemicals all day, and i still was very cautions about how i was doing this. Anyone else who trys it i would advise to wear at least nitirle/latex gloves and some sort of overcoat. (i'm making it sound more dangerous than it is but better safe than sorry!).
The first stage was to gather the ingredients. They are:
First step is to mix the NaOH with the Methanol, which will take a while (do this in a glass or metal container as the NaOH can eat away at plastic and it also gets quite warm). This forms a cloudy solution called methoxide, which is basically a nerve toxin. In high concentrations this kills living cells before they have time to feel pain - nasty stuff. This concentration is relatively safe but is still highly flammable and should be handled with the utmost care. If you get any on you or your clothes, rinse it off thoroughly, wash clothes and if it was a large amount, see your doc!
The methoxide is used to replace the fatty acids in the oil with methanol, a process called transestrification. This drops the viscosity ALOT and makes it much more flammable! The by-product of this is just glycerin (soap) which needs to be removed eventually. Although i've not looked into the exact chemistry is should be available online somewhere.
Once the methoxide is ready, heat your oil to 60C, then move to your reactor vessel, which should be glass again.
Thumbs up didnt really work!
1L of veg oil and 200ml of Methoxide (200ml Methanol + 3.5g NaOH) makes ~ 1L of bio, and some soap (glycerin)!
Now pour the methoxide into the oil and shake vigarously for 10-15 seconds to get it properly mixed. Your mixture should go a banana milkshake/custard colour as the methoxide and oil mix, then as the reaction begins it will go a dark yellowy/brown. Pics shows phase seperation after pouring, just after mixing then after 15mins.
Phases Separate (Wee )
Banana Milk :yuck:
15mins later (Bad Wee )
The warmer you keep it (around 50C) the better as this speeds up the reaction, and keeps the viscosity of the oil down, allowing the two products to separate.
The last pic shows 1 hour after mixing, and a very visible, thick glycerin layer at the bottom.
Next i need to leave the reaction to finish, and all the glycerin to separate out. Then i'll tip the bottle upside down and find some way to get all the by-product out, and take the biodiesel into work to run some viscosity measurement/water tests etc.
From here, i could prob just put it in with a load of normal diesel and it'd be fine. If i wanted to run higher concentrations i would need to wash/dry the product thoroughly, then filter it, but the kit for this costs wedge so would only go to that stage if/when i feel a larger scale run would be worth it!
I hope this helps anyone who was thinking about this, or just provides a good read for a few nerds like me!
Will continute to update over the W/E!
Thanks for listening
I'm doing this purely as a proof of principle exercise. If i can produce a small quantity of a rough product using nothing more than some chemicals then i figure scaling it up with proper equipment shouldnt be too difficult, and then move to WVO.
I'm a professional research scientist who works with hazardous chemicals all day, and i still was very cautions about how i was doing this. Anyone else who trys it i would advise to wear at least nitirle/latex gloves and some sort of overcoat. (i'm making it sound more dangerous than it is but better safe than sorry!).
The first stage was to gather the ingredients. They are:
- Veg Oil (any old cheap rubbish will do but i ended up using sainsburys at £1.20/l :bang
- Methanol (you need approx 1/5th by volume of veg oil, but up to 1/4 is fine)
- Sodium hydroxide (for pure veg oil you need ~3.5g/l of oil
First step is to mix the NaOH with the Methanol, which will take a while (do this in a glass or metal container as the NaOH can eat away at plastic and it also gets quite warm). This forms a cloudy solution called methoxide, which is basically a nerve toxin. In high concentrations this kills living cells before they have time to feel pain - nasty stuff. This concentration is relatively safe but is still highly flammable and should be handled with the utmost care. If you get any on you or your clothes, rinse it off thoroughly, wash clothes and if it was a large amount, see your doc!
The methoxide is used to replace the fatty acids in the oil with methanol, a process called transestrification. This drops the viscosity ALOT and makes it much more flammable! The by-product of this is just glycerin (soap) which needs to be removed eventually. Although i've not looked into the exact chemistry is should be available online somewhere.
Once the methoxide is ready, heat your oil to 60C, then move to your reactor vessel, which should be glass again.
Thumbs up didnt really work!
1L of veg oil and 200ml of Methoxide (200ml Methanol + 3.5g NaOH) makes ~ 1L of bio, and some soap (glycerin)!
Now pour the methoxide into the oil and shake vigarously for 10-15 seconds to get it properly mixed. Your mixture should go a banana milkshake/custard colour as the methoxide and oil mix, then as the reaction begins it will go a dark yellowy/brown. Pics shows phase seperation after pouring, just after mixing then after 15mins.
Phases Separate (Wee )
Banana Milk :yuck:
15mins later (Bad Wee )
The warmer you keep it (around 50C) the better as this speeds up the reaction, and keeps the viscosity of the oil down, allowing the two products to separate.
The last pic shows 1 hour after mixing, and a very visible, thick glycerin layer at the bottom.
Next i need to leave the reaction to finish, and all the glycerin to separate out. Then i'll tip the bottle upside down and find some way to get all the by-product out, and take the biodiesel into work to run some viscosity measurement/water tests etc.
From here, i could prob just put it in with a load of normal diesel and it'd be fine. If i wanted to run higher concentrations i would need to wash/dry the product thoroughly, then filter it, but the kit for this costs wedge so would only go to that stage if/when i feel a larger scale run would be worth it!
I hope this helps anyone who was thinking about this, or just provides a good read for a few nerds like me!
Will continute to update over the W/E!
Thanks for listening
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