Hello Emre, Rafal et al. I have to say that I partially disagree with some of your statements. The limit of FFA for a flawless trans-esterification is drawn at 5mg KOH/g of oil. Any value above will demand pre-treatment of the oil. It is always important to check the water content, which should be below 0,5%. Try to get hold of a water-in-oil test kit for quick determination. If we are talking about the EN standard, it is always necessary to process the oil/catalyst/methanol mix for 90 minutes to obtain the right values for tri- di- and monoglycerides. And - this assumes that you have correct stochiometric conditions and no methanol losses during processing. As for the phophatides and the chlorophyll compounds, my experience is that these are not very important for the processing result, unless the values of these are extremely high (thousands of ppms). If so, the oil is usually very dark. Totally refined oil, on the other hand, may have preservatives added, and some of these will eat catalyst. So, good oil quality is a tricky thing. Best of luck to you ! Jan Warnqvist AGERATEC AB
+ 46 554 201 89 +46 70 499 38 45 ----- Original Message ----- From: "EMRE ELMAS" <[EMAIL PROTECTED]> To: <biofuel@sustainablelists.org> Sent: Sunday, August 20, 2006 10:15 PM Subject: Re: [Biofuel] tirating a virgin oil > Dear Rafal, > > First of all, as long as you use cheap oil you should always be prepared to > deal with much more FFA and water than it should normally contain. I think > your emulsion problem occurs as a result of highly contained water. If that > is the problem you should first dry the oil then process the reaction. > > Also if you use crude oil you should be very careful about the chemicals, > such as lesitine, in the oil. So always try to use degummed oil, if you have > to process crude oil. > > Another thing is, as you probably know, approximately 95 - 97 % of the > reaction is completed in the first 35 minutes, so you do not have to wait > for 2 hours. Also the alcohol boils at 65 C and the closer you get to that > point, the more alcohol you will lose at the time you need it the most for > the reaction. This prevents you to complete the reaction 100 %. > > As I mentioned above if you just watch the content of water and the other > impurities in the oil you will be fine. > > Hopefully the information works for you. I am looking forward to hear from > you soon. > > Best wishes, > > Emre ELMAS > Mobile: +90 533 517 72 45 > > > > > > >From: Rafal Szczesniak <[EMAIL PROTECTED]> > >Reply-To: biofuel@sustainablelists.org > >To: biofuel@sustainablelists.org > >Subject: [Biofuel] tirating a virgin oil > >Date: Sun, 20 Aug 2006 19:31:26 +0200 > > > >Hi, > > > >Recently I've came through problems with testing a cheap virgin oil > >in my test processor which every time ended up with incomplete reactions > >(emulsion problems). I did make the process longer (2 hours) and at > >higher temperature (60-63 degC) - still nothing, though by product > >separation is very nice. > > > >Today, I tried to titrate the oil and - to my surprise - it took 0.925ml > >of KOH solution. This was my first experience with titration, so I can > >also tell that the phenolophtalein solution turned pale (but noticable) > >magenta for about 15 secs (as described at JtF) after 0.925ml. After > >adding 1.05ml the colour got more intensive for longer time. > > > >My main question is - is it normal in case of cheap oils ? > >I suppose they contain (as other oils) some amount of FFAs, but so much ? > > > >Additional matter is whether I got titration right. I mean, interpreting > >the colours. > > > >I'm running out of ideas what could be wrong in the process, so any > >help is appreciated. > > > > > >-- > >cheers, > > > > Rafal Szczesniak **mir[at]diament.iit.pwr.wroc.pl > > Samba Team member mi***[at]samba.org > >+---------------------------------------------------------+ > > *BSD, GNU/Linux and Samba http://www.samba.org > >+---------------------------------------------------------+ > > > > > >_______________________________________________ > >Biofuel mailing list > >Biofuel@sustainablelists.org > >http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org > > > >Biofuel at Journey to Forever: > >http://journeytoforever.org/biofuel.html > > > >Search the combined Biofuel and Biofuels-biz list archives (50,000 > >messages): > >http://www.mail-archive.com/biofuel@sustainablelists.org/ > > > > _________________________________________________________________ > Don't just search. Find. Check out the new MSN Search! > http://search.msn.click-url.com/go/onm00200636ave/direct/01/ > > > ---------------------------------------------------------------------------- ---- > _______________________________________________ > Biofuel mailing list > Biofuel@sustainablelists.org > http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): > http://www.mail-archive.com/biofuel@sustainablelists.org/ > > _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/