Allow me to make a few responses to earlier remarks:

"You forgot to mention the side reaction that is also making soap out of the oil/biodiesel and the NAOH/KOH that is catalyzing the main reaction that makes biodiesel."

I did not. I stated "Although most of it is,(refering to a catalyst) some is acting as a reagent neutralizing any free fatty acids." This is the side reaction, in chemical terms, that is making the soap.

In response to:
Then a chemist on this forum and another forum both figured it out independantly to be around 12.5%/125ml methanol"

This is not "stoichiometry", which was the issue. This is still merely an approximation of MeOH used in the reaction because of the variation among oils. Stoichimetry has to do with exact molecular ratios not amounts "around"
a particular value. Based on data I am aware of, the value of 150ml is high. I wasn't arguing that point but only reflecting on the issue being made with the use of the term "stoichiometry."

I'll also grant the fact that lines aren't made of Natural rubber, but the author's intent was to note that the lines in autos may need to be upgraded to other more resistant materials.

These comments merely emphasize the point I was making in the first place. Nitpicking a few things to death while overlooking a very fine job of putting together a manual of information distributed freely over the web seems to be a bit misdirected.

I am delighted to see that people are indeed interested in the science of the process and understanding what is occuring. Certainly experience provides knowledge and value. I respect the vast amount of information shared on this forum.

I do not intend to get into a debate however with anyone about side issues as this only distracts from the work done by Hans.

Hans, I downloaded your manual, read it, and found it to be very informative. It looks like the feed back has been good and I look forward to your update.

Let me offer just a little "layman's" clarification and expand on the information posted by Foxden.

quote:

Originally posted by Foxden:
. . .
"You forgot to mention the side reaction that is also making soap out of the oil/biodiesel and the NAOH/KOH that is catalyzing the main reaction that makes biodiesel."

I did not. I stated "Although most of it is,(refering to a catalyst) some is acting as a reagent neutralizing any free fatty acids." This is the side reaction, in chemical terms, that is making the soap.
. . . .

If the oil and other reagents started out completely dry, then the soap-making side reaction would take place within a few moments of initial addition of the reagents. All FFA would quickly be neutralized, with one of the by-products being soap, by the base catalyst.

Assuming the titration was done correctly, the "titration amount" of catalyst is consumed in the initial soap-maiking FFA conversion step. The base amount of catalyst would still be available to the reaction. The base amount would no longer undergo any more destruction during the remainder of the reaction.

But, (there is always a but) the presence of any water in the system causes hydrolysis of the glyceride molecule. Water in the reaction "breaks" a fatty acid chain from the glyceride molecule. As soon as the fatty acid chain breaks, it becomes a FFA. The newly formed FFA combines with the catalyst to make soap. This consumes catalyst. The only catalyst available at this time in the reaction is the "base" amount. As hydrolysis occurs additional catalyst is consumed. As the soap is formed, the water molecule is released back into the solution where it immediately attacks another fatty acid chain.

This second "side reaction" continues to make soap until the catalyst is completely consumed.

Fortunately the hydrolysis reaction is relatively slow compared to the transesterification reaction. So only a small percentage of catalyst is consumed. However, it is important to design your system to provide high mixing energy, proper operating temperatures, and short enough reaction times to achieve conversion before the catalyst is destroyed. Starting a reaction and letting it run overnight, or starting a reaction, then stopping it, then restarting several hour later are not good practices.

The other important point is to limit the amount of water in the system. There will always be water in the methanol-catalyst mixture, because water is chemically formed when the catalyst is dissolved in the methanol. This water can not be controlled and will always be present.

But, for best results a home-brewer should always use dry oil. Elimination of water in the oil is one of the few operations a home-brewer can do that has such a large positive effect on his finished product.

I agree completely and think this is the kind of comments that move things forward. Well said.

Yes !

I understand this completely. This is saying a great deal given my non-chemistry background, and is the kind of information I'm trying to convey in the background chemistry section of the document: a simple explanation to other non-chemists in order to provide some depth to the simple recipes that we might otherwise take on faith.

To follow up on your comment:

“However, it is important to design your system to provide high mixing energy, proper operating temperatures, and short enough reaction times to achieve conversion before the catalyst is destroyed.”

I take it this is why getting the oil heated is important. Specifically, the added energy helps promote the rate of transesterification (through mixing) thus minimizing the impact that water can have on the hydrolysis of glycerin and release of FFA. Correct? That would be a very valuable observation for version 1.04 in explaining the need for dry oil and heating, and is certainly the kind of input I’m looking for.

Thanks Foxden, Producer, and others.

As for nitpicking, I have to admit that I was initially concerned about the full body of work being discounted over something like the incorrect use of the word "stoichiometry". However, I got over it pretty quick when I realized that these comments require and investment of time on behalf of individuals such as Tilly who probably know more than me in such matters. Where appropriate, these can add value credibility to the document. On that note, I look forward to Tilly’s and others future observations even if they do come off a little harsh Content is certianly more important than tone, although encouragement is always welcome.

I will share your observations with others in the homebrew community who know more than I to make sure it is worded correctly in version 1.04.

Hans Huth

Hello Foxden
Producer explained to you the Other reaction that you did not seem to know about that is producing soap.

If you readThis Thread you will understand the side reaction I am talking about

VER 1.04 posted to http://www.biod101.com/

Added parts list and design for a bucket-funnel for the simple transfer of oil to an appleseed processor. For the update, please see the section associated with the diagrammed appleseed processor.

Reflected input from recent postings on the importance of dry oil and mixing; for update, see section dealing with biodiesel chemistry. (Thank you Producer and Foxden for your valuable input).

HH

Thank you.

Friends –

On June 15th, I will be posting revisions to the Biodiesel 101 Manual (version 1.05).

Revisions will include:

1. Corrections and recommended improvements to version 1.04 thanks to an extensive review by Foxden (http://biodiesel.infopop.cc ) (Thank You!).

2. Summary of a conversation with Craig Gross- Zoning Administrator for the City of Tucson, Arizona regarding homebrew operations within city limits.

3. Pictures of an inexpensive biodiesel filtration system developed by Steve Fischer – a friend and local homebrewer here in Tucson, Arizona.

I hope to release version 1.06 next month. In that release, I hope to summarize my experiences with acid esterification yet to be undertaken.

The latest revisions are available at this URL:

http://www.biod101.com

Regards –

Hans Huth

quote:

Originally posted by Foxden:
These comments merely emphasize the point I was making in the first place. Nitpicking a few things to death while overlooking a very fine job of putting together a manual of information distributed freely over the web seems to be a bit misdirected.

I am delighted to see that people are indeed interested in the science of the process and understanding what is occuring. Certainly experience provides knowledge and value. I respect the vast amount of information shared on this forum.

I do not intend to get into a debate however with anyone about side issues as this only distracts from the work done by Hans.

I concur with these statements whole heartedly. I've read this thread with sincere interest.

While generalized reactions can be presented as fact, the realities of the processes are quite complex given WVO is a mixture, hence the recognition of practical experience. Hans, excellent job; Foxden, producer, RickDaTech and others - points and insights well taken. Hans, I'll use your manual as a primer with my general chemistry students. The thread in general will demonstrate how scientist are objective and open minded, vs. non scientist whom are often closed minded and dogmatic (not that these are necessarily bad traits in totality but they more often then not hinder the advancement of knowledge). Unfortunately this does commonly occur in science. Debates being used to promote egos are deleterious to the sharing of information. This is a thread, to date, that can be seen as one of progress and of benefit to the BD community at large.

Conveying and assimilating information requires perspective. For the sake of clarity on my own part I am going to try to separate speculation from fact when posting to threads moving forward. Replies that are prefaced with "assumptions" will be stated as such for substantiation of the subsequent reply ... maybe this will curtail some of the "nit picking". Constructive criticism on any post I make is surely welcome as I don't want to disseminate incorrect or inaccurate information. I've never told my wife or child "I told you so", nor belittled the honest effort of anyone - should I do so here fill free to correct me.

"john galt" point well taken.

Again Hans, excellent job. I look forward to your updates.

Thanks oprogue and others,

With respect to your comment on perspective, I agree that it is important to clarify the same. With respect to my own perspective, I try to make clear that I am not an expert in this topic and am really only trying to convey my experiences as a foundation for others who may decide to pursue this activity. The same is stated in the biod101 homepage as well as the disclaimer, specifically:

"My own manual is written from the point of view of someone pursuing homebrewing in Tucson, Arizona. My document is being provided free of charge and I make no promises about its overall accuracy and completeness"

... and in the disclaimer: "I am not a legal or chemical expert in the manufacture and/or use of biodiesel. This volume is based for the most part on my own experience and in no way is comprehensive of the entire subject."

and finally: "My intention here is to demonstrate that making biodiesel from waste vegetable oil requires many considerations that are not well documented in some of the kits made available online. Hopefully, this document will bring those considerations to light as I understand them, and will dissuade some from getting involved in an activity which they may not be prepared for."

As such, I hope I've made it clear that my goal is simply to share my experience pursuing this activity. That experience is based in large part on my concerns discussed under the topic "Is it worth it?" (p 187).

I appreciate the recommendations and corrections provided via this forum- particularly from those who know more than me. In fact, reflecting these corrections in future revisions is a responsibility I take seriously.

Everyonoe's input is welcome. Perhaps the price one pays for pursuing that input is occasionally having to put up with the unnecessary noise that sometimes accompanies corrections. Being relatively new to this kind of a forum, I've learned that I just have to filter the noise out and just focus on the content.

Everyone - please keep the reviews and the suggestions coming either through a private message or through this public forum. I'm on revision 1.05 thanks in large part to those who have helped through this most excellent venue.

Hans Huth

Hello Hans
Welcome back to the forum!
I see you have returned to advertise your download again.

Once again I extend to you a sincere invitation to become an active member of this forum and think of us as more than just a place to advertise your download.

Out of curiosity, have you received much money from the donations request?

First off - tilly, you are being a jerk.

Secondly - Has anybody heard from girl mark lately?

Thirdly - As a suggestion, to Hans, I would avoid using terms which have specific scientific meanings incorrectly - it doesn't help anyone out. As tilly has pointed out about a thousand times, using a term like stochiometric in relation to the catalyst represents a gross misconception of what the term means and even how the process as a whole works - this casts doubt on the accuracy of the material which lies within the rest of the work. Which, correct me if i'm wrong, represents Tilly's entire point of why he was so dogmatic about pursuing it to a point of clarification.

I went to the site 101 bio fuels , and clicked every link , did not find the down load ?
I miss a lot of things , just need to find it .
Thanks John

I found it , I do give disclaimers much value , because , I think that we should be responsible for are own actions , not others , if I break it , I can only ***** to myself .
Thanks John

I hope it is useful to you John,

For others who may have trouble finding the download link, note that you must click through the disclaimer in order to download the document. I wish I could make this easier, but my exposure to liability requires me to take such measures.

I'll be on a roadtrip for the next three weeks, so for those of you who post suggestions, please note I won't be able to incorporate them for some time. However, a link to this thread has been placed on my revisions page so that your input can be reviewed by those willing to take the trouble.

I'll be back after July 7th, and I will do my best to get another revision out by mid August.

Cheers

quote:

Originally posted by Dogma721:
Secondly - Has anybody heard from girl mark lately?

Thirdly - As a suggestion, to Hans, I would avoid using terms which have specific scientific meanings incorrectly - it doesn't help anyone out. ...

I was hoping to run into her in Pittsboro long enough to check thing out there.

Given HH prefaced his work, and that a term has caused such a roar, perhaps from a literary view it should be left in place. If someone is interested and wants to find out what it implies in depth then they can seek that information out. Otherwise the term will be glossed over as the reader will merely move on to the content they are interested in.

I wish my students would take as much interest!

This debate has been good (abet interpretation of the tone of some of the replies) and enlightening.

thegreenbeat,

One way to lower the endless effort you have to put into this.

You might consider putting this all on Wikipidea. Im no expert in that site but if Im not mistaken others can add input, make changes etc. Therfore folk like Tilly and others who; like you say; know more than you, can go in and correct it, tweak the wording to make things more clear etc.

Sorry wish I knew more about Wikipedia to help you out. With what little I know it sounds like it might just work to everyones benefit to go that route.