Biopowered - vegetable oil and biodiesel forum
Biodiesel => Chemistry and process => Topic started by: RobPerrie on April 25, 2022, 10:52:44 AM
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I've forgotten the formula for the asm no tit ...i have 36 litres of unprocessed oil and forgot the next stage, not made for ages and now got to do lots of driving..any one help and sir Nigel, you out there
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Just use the base for Sodium 5.0 and as your ASM is 30% just divide by 0.3.
So 36 litres x 5 = 180 divided by 0.3 = 600 mls ASM.
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Just use the base for Sodium 5.0 and as your ASM is 30% just divide by 0.3.
So 36 litres x 5 = 180 divided by 0.3 = 600 mls ASM.
180g of NaOH is 4.5 moles (MW 40).
180g of NaOCH3 is 3.33 moles (MW 54). The lack of water and resultant higher efficiency means you should get away with the lower quantity but to have the equivalent of 5.0g/L NaOH you would need 243g of NaOCH3 so 810 mls.
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I will bow to your greater knowledge of chemistry Paul. However if Robs 36 litres is for his 2nd reaction (ie only requires base amount ) then from experiance the 810mls is well overdosed.
Question for you. When methoxide heats up during mixing is it due to water being formed, if it is then ASM also heats when being mixed with methanol?
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I always used a base of 3g/Lt x 5 and a methanol ratio of 15%
So 3 X 5 X 36 = 540ml of ASM. 15% of 36lt = 5.4lt.
Place 540ml ASM in your container and make up to 5.4 ltr with meth.
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I will bow to your greater knowledge of chemistry Paul. However if Robs 36 litres is for his 2nd reaction (ie only requires base ampunt ) then from experiance the 810mls is well overdosed.
Question for you. When methoxide heats up during mixing is it due to water being formed, if it is then ASM also heats when being mixed with methanol?
Dave,
If you are refering to dissolving NaOH in methanol the formation of water may be exothermic, but there is also the equivalent of hydration energy being released. If you dissolve some NaOH in a small amount of water it also gets hot (enough to burn you). In this case there is no water formation just the hydration energy being released.
I suspect the formation of water is lower energy than the solvation.
Dissolving crystalised Sodium Methoxide in methanol is also likely to be exothermic (I haven't actually checked). Adding 30% methoxide to methanol may be exothermic but probably less so than dissolving the solid.
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I will bow to your greater knowledge of chemistry Paul. However if Robs 36 litres is for his 2nd reaction (ie only requires base ampunt ) then from experiance the 810mls is well overdosed.
Question for you. When methoxide heats up during mixing is it due to water being formed, if it is then ASM also heats when being mixed with methanol?
Dave,
If you are refering to dissolving NaOH in methanol the formation of water may be exothermic, but there is also the equivalent of hydration energy being released. If you dissolve some NaOH in a small amount of water it also gets hot (enough to burn you). In this case there is no water formation just the hydration energy being released.
I suspect the formation of water is lower energy than the solvation.
Dissolving crystalised Sodium Methoxide in methanol is also likely to be exothermic (I haven't actually checked). Adding 30% methoxide to methanol may be exothermic but probably less so than dissolving the solid.
I agree that 810mls would be more than neccesary, especially on a 2nd stage reaction, however JamesRL is not from Yorkshire (as far as I know) yet seems to be even more stingy ;D
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RobPerrie, there you go mate, take your pick!
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i sooo miss you lot, i didnt get any notification you replied, i need to fix this thing and thank you everyone, James, didn't see you this time coming back from the boys football tournament...
does the meet still happen this year, normally im out of the country working, but not this year until july..