Re: [Biofuel] Acid-base chemistry
lol, yeah, moles for sure are kind of tricky. precisely because of the things you mention. (i dropped chem in college. there was no way i was going to pass if i stuck it out.) thanks for sharing your impression of the youtube guy. sorry if it was waste of your time. ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Acid-base chemistry
Hi Chris Thanks! But... keith, don't know if this will help, but. . .: http://www.youtube.com/user/khanacademy#p/c/166048DD75B05C0D/10/gfBcM3uvWfs Emperical? H amu is 1.008 but he reads it out as one-point-oh-oh-oh-eight. And so on, much sloppiness! I thought it was rather poor, I'm sure you can find better resources for brushing up your math skills. Strange to tell, but my high-school chemistry lessons never once mentioned moles. :-( (Don't ask me what kind of school I went to or I'll tell you.) I can see that moles are useful, and I can figure it out, but moles only concern mass, and what I often need is volume. How many people would be able to follow titration instructions eg if the quantities were given in moles? Not a lot, I think. And for weight, a simple measure in grams is clearer. Going from moles to volumes isn't so easy, the SG ratios make it complicated (and it turns out SG is itself controversial, 1cc H2O @ 4degC weighs 1g isn't the gold standard it used to be). I did get a result, I think it's right, but I'm not sure, and not quite sure that it works like that anyway. 1 ml H2SO4 + 80 ml CH3OH -- (I think) ? CH4SO4 + ? H2O (Not sure that's right either.) Can you do it? Give your math some practice. :-) Periodic table of elements: http://www.chemicalelements.com/ Avocado's cucumber: http://www.chemistry.co.nz/avogadro.htm Density, mass, SG of Liquids (useful table): http://www.simetric.co.uk/si_liquids.htm Mole (FWIW): http://en.wikipedia.org/wiki/Mole_(unit) All best Keith and: http://www.youtube.com/user/khanacademy#p/c/166048DD75B05C0D/11/AsqEkF7hcII maybe it'll give you what you need to feel more confident doing it yourself? i've been meaning to check some of this guy's stuff out myself (really need to revisit a lot of high school math), but haven't gotten around to it yet. -chris On Sun, Apr 18, 2010 at 1:27 PM, Keith Addison [EMAIL PROTECTED]wrote: I have difficulty with moles. I do know how to figure it out, in theory, but I'm not confident of the result. ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Acid-base chemistry
Hello Keith. Moles means molecules. There is one water molecule formed for each molecule of fatty acid alkylated. It is true that some water is produced during saponification of free acidity and it is also true that water is formed when mixing NaOH or KOH in an alcohol. But neither of these reactions are esterification or transesterification reactions.. It is considered that the transesterifiction reaction takes place in two or more steps, where the first step is the collapse of the glycerine-formed ester (the triglyceride etc) forming free glycerine and free acidity. Water is consumed in that step. In another step the new esters are formed where the equal amount of water is released. Conclusion: Some free water is good for the first step of the reaction. Does it make sense ? - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Sunday, April 18, 2010 7:27 PM Subject: Re: [Biofuel] Acid-base chemistry Hello Jan Thankyou! The acid esterification produces water with 1M /M alkylated fatty acid. I have difficulty with moles. I do know how to figure it out, in theory, but I'm not confident of the result. Would you mind writing it as a formula equation, if that's the right term: A + B -- D + E Moles gives quantities though, which I'd like to know. Is it possible to translate 1M /M alkylated fatty acid into ml of water per litre of oil or something similar? The trans-esterification does not produce any water, We've had people saying it does, and others that it doesn't. It's been said that some water is produced by the saponification of free fatty acids, though it's very little, and someone else said some water might be formed during the reaction that produces the methoxide: CH3OH + KOH --- CH3OK + H2O or CH3OH + NaOH --- CH3ONa + H2O Any comments? but some water present (0,1%) is necessary to make the process run well. I didn't know that. Can you explain how it works? I did know that esterification will also perform some transesterification if it has the chance, but it's slow. Thanks again Jan - all best to you Keith The acid esterification produces water with 1M /M alkylated fatty acid. This process will also perform trans-esterification assuming that there is some material to trans-esterify and that the operator in question lets the process continue. With best regards Jan W - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Saturday, April 17, 2010 11:58 AM Subject: [Biofuel] Acid-base chemistry Hello all A question... Even when everything is dry, including the oil, the transesterification process itself produces some water, though not very much. IIRC acid esterification also produces water, I think more water than transesterification does, and via a different process. Does anybody know if that's correct, and what the chemical equations are? With KOH and H2SO4. Thanks! All best Keith ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/ ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Acid-base chemistry
keith, don't know if this will help, but. . .: http://www.youtube.com/user/khanacademy#p/c/166048DD75B05C0D/10/gfBcM3uvWfs and: http://www.youtube.com/user/khanacademy#p/c/166048DD75B05C0D/11/AsqEkF7hcII maybe it'll give you what you need to feel more confident doing it yourself? i've been meaning to check some of this guy's stuff out myself (really need to revisit a lot of high school math), but haven't gotten around to it yet. -chris On Sun, Apr 18, 2010 at 1:27 PM, Keith Addison [EMAIL PROTECTED]wrote: I have difficulty with moles. I do know how to figure it out, in theory, but I'm not confident of the result. -- next part -- An HTML attachment was scrubbed... URL: /pipermail/attachments/20100419/4724d6bd/attachment.html ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Acid-base chemistry
Hello again Jan Thanks for the explanation. Hello Keith. Moles means molecules. Yes, or molecular weights. My problem is with translating moles to quantities, such as ml and litres. Which brings in specific gravity / relative density... :-( I can manage though. I arrived at a figure of the acid esterification step producing 17.3 ml of water per litre of oil processed (rapeseed), 1.73%. I doubt it's that precise, but it should be something like that. There is one water molecule formed for each molecule of fatty acid alkylated. It is true that some water is produced during saponification of free acidity and it is also true that water is formed when mixing NaOH or KOH in an alcohol. But neither of these reactions are esterification or transesterification reactions.. No, but the water is there nonetheless. It is considered that the transesterifiction reaction takes place in two or more steps, where the first step is the collapse of the glycerine-formed ester (the triglyceride etc) forming free glycerine and free acidity. Water is consumed in that step. In another step the new esters are formed where the equal amount of water is released. Conclusion: Some free water is good for the first step of the reaction. Does it make sense ? Yes it does. So in acid-base processing, the acid esterification stage should provide the water needed for the first step of the base transesterification stage, very convenient. The water released in the final stage of transesterification should end up in the glycerine byproduct layer, or most of it anyway, and washing and settling should remove the rest. Without the preceding acid esterification stage, could some of the water required in the first step of transesterification be provided by the water formed in mixing the methoxide? I'd imagine that water formed during saponification would be in the by-product layer rather than available to help initiate transesterification. Interesting, Jan - thanks very much. All best to you Keith - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Sunday, April 18, 2010 7:27 PM Subject: Re: [Biofuel] Acid-base chemistry Hello Jan Thankyou! The acid esterification produces water with 1M /M alkylated fatty acid. I have difficulty with moles. I do know how to figure it out, in theory, but I'm not confident of the result. Would you mind writing it as a formula equation, if that's the right term: A + B -- D + E Moles gives quantities though, which I'd like to know. Is it possible to translate 1M /M alkylated fatty acid into ml of water per litre of oil or something similar? The trans-esterification does not produce any water, We've had people saying it does, and others that it doesn't. It's been said that some water is produced by the saponification of free fatty acids, though it's very little, and someone else said some water might be formed during the reaction that produces the methoxide: CH3OH + KOH --- CH3OK + H2O or CH3OH + NaOH --- CH3ONa + H2O Any comments? but some water present (0,1%) is necessary to make the process run well. I didn't know that. Can you explain how it works? I did know that esterification will also perform some transesterification if it has the chance, but it's slow. Thanks again Jan - all best to you Keith The acid esterification produces water with 1M /M alkylated fatty acid. This process will also perform trans-esterification assuming that there is some material to trans-esterify and that the operator in question lets the process continue. With best regards Jan W - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Saturday, April 17, 2010 11:58 AM Subject: [Biofuel] Acid-base chemistry Hello all A question... Even when everything is dry, including the oil, the transesterification process itself produces some water, though not very much. IIRC acid esterification also produces water, I think more water than transesterification does, and via a different process. Does anybody know if that's correct, and what the chemical equations are? With KOH and H2SO4. Thanks! All best Keith ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Acid-base chemistry
Hello Jan Thankyou! The acid esterification produces water with 1M /M alkylated fatty acid. I have difficulty with moles. I do know how to figure it out, in theory, but I'm not confident of the result. Would you mind writing it as a formula equation, if that's the right term: A + B -- D + E Moles gives quantities though, which I'd like to know. Is it possible to translate 1M /M alkylated fatty acid into ml of water per litre of oil or something similar? The trans-esterification does not produce any water, We've had people saying it does, and others that it doesn't. It's been said that some water is produced by the saponification of free fatty acids, though it's very little, and someone else said some water might be formed during the reaction that produces the methoxide: CH3OH + KOH --- CH3OK + H2O or CH3OH + NaOH --- CH3ONa + H2O Any comments? but some water present (0,1%) is necessary to make the process run well. I didn't know that. Can you explain how it works? I did know that esterification will also perform some transesterification if it has the chance, but it's slow. Thanks again Jan - all best to you Keith The acid esterification produces water with 1M /M alkylated fatty acid. This process will also perform trans-esterification assuming that there is some material to trans-esterify and that the operator in question lets the process continue. With best regards Jan W - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Saturday, April 17, 2010 11:58 AM Subject: [Biofuel] Acid-base chemistry Hello all A question... Even when everything is dry, including the oil, the transesterification process itself produces some water, though not very much. IIRC acid esterification also produces water, I think more water than transesterification does, and via a different process. Does anybody know if that's correct, and what the chemical equations are? With KOH and H2SO4. Thanks! All best Keith ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
[Biofuel] Acid-base chemistry
Hello all A question... Even when everything is dry, including the oil, the transesterification process itself produces some water, though not very much. IIRC acid esterification also produces water, I think more water than transesterification does, and via a different process. Does anybody know if that's correct, and what the chemical equations are? With KOH and H2SO4. Thanks! All best Keith ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
Re: [Biofuel] Acid-base chemistry
Hello Keith and all. The trans-esterification does not produce any water, but some water present (0,1%) is necessary to make the process run well. The acid esterification produces water with 1M /M alkylated fatty acid. This process will also perform trans-esterification assuming that there is some material to trans-esterify and that the operator in question lets the process continue. With best regards Jan W - Original Message - From: Keith Addison [EMAIL PROTECTED] To: biofuel@sustainablelists.org Sent: Saturday, April 17, 2010 11:58 AM Subject: [Biofuel] Acid-base chemistry Hello all A question... Even when everything is dry, including the oil, the transesterification process itself produces some water, though not very much. IIRC acid esterification also produces water, I think more water than transesterification does, and via a different process. Does anybody know if that's correct, and what the chemical equations are? With KOH and H2SO4. Thanks! All best Keith ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/ ___ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/sustainablelorgbiofuel Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (70,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
