Hello Doug. Keith has made an excellent input to you questions but I felt it necessary to add some aspects of your problem: The rule no1 when taking samples is to make sure - as possible- that the sample is representative for the batch. This sounds simple, but if you are dealing with high water content together with high FFA levels you will have different titration values if sampled from the top or from the bottom. If there are detergents in the oil, this actually may help. It is a disadvantage when washing the biodiesel though. By using IPA for titration, the general idea is to have one clear phase consisting from IPA, water, KOH (or NaOH) and oil. The EN standard for determination of acid number which is likewise determined by titration strongly recommends that the amount of IPA should be increased if the solution becomes cloudy or turbid. By using methanol for titration, you are out of standard procedure. And - possibly annoying Keith - the EN requirement for a good titration is that the solution stays magenta for at least 15 seconds. Good luck to you further on ! With best regards Jan Warnqvist AGERATEC AB
[EMAIL PROTECTED] + 46 554 201 89 +46 70 499 38 45 ----- Original Message ----- From: "Keith Addison" <[EMAIL PROTECTED]> To: <biofuel@sustainablelists.org> Sent: Thursday, August 11, 2005 9:38 AM Subject: [Biofuel] Re: A beginners titration question > Hello Doug > > >Hello group, > >I am a beginner in the conversion of WVO to BD and I have been > >having trouble with my titration process. On JTF there are 2 > >reference documents on titration which I have been using as my guide. > > There's more than that there about titration. > > >However, I don't seem to get consistent results. For example, One > >time I will get 1.55ml and the second time I get 3.22 ml using WVO > >from the same batch and drawing from the same solution of NaOH and > >water. > > > >First is that kind of variability to be expected? > > No. > > >Second I noticed in reviewing the tritration documents again, that > >isopropyl alcohol is specifed. > > But how could you not have noticed that the first time round? > Everywhere is says so. > > > I have been using the same methanol that I use in the conversion > >process. Prefacing this with "I ain't no chemist", Is that the > >source of my problem? If that is the case can someone explain why > >the titration is done with one type of alcohol when the process is > >run with a different one? > > I also ain't no chemist, very few of us are chemists, but we can > learn, and do. I can't give you a technical comparison of the effects > of different alcohols, but why depart from established practice when > you're just starting? It doesn't make a lot of sense anyway, > titration and processing have different purposes, with titration > you're only finding out how much acid will have to be neutralised, > not processing the WVO. The result of the titration is applied to the > subsequent processing in the form of the amount of lye required, not > the kind of alcohol to use. If you assume that the two different > processes should use the same alcohol then why don't you also assume > that they should use it in the same proportions? - ie 10 litres of > 99%+ isopropyl alcohol per one litre of WVO to be processed? > > Anyway, it is possible to use isopropyl alcohol to make biodiesel, > called branched-alkyl esters, which have the advantage of much > improved cold-weather properties. There's discussion of this in the > list archives, using either isopropyl alcohol or butanol. But it's > not for homebrewers, though many have tried - it's laboratory-level > stuff, patented but not used, nobody is using these techniques yet > AFAIK. > > >Also I seem to be having difficulty keeping the WVO and alcohol > >mixed during the titration process, which would be what I would > >attribute to the variation in the results. > > I don't think so. > > >I have been carrying out the titration in a test tube and shaking > >it after each drop, but the oil still seems to settle out. > > Stirring is better. Did you warm the mixture first (and the 0.1% NaOH > solution)? Use something wider than a test tube that you can stir. > > >And even when they are mixed it is a cloudy white solution, not > >clear as the JTF documents indicate. > > They do not indicate that. What they say is that it should be clear > (thoroughly mixed) BEFORE you start adding the 0.1% NaOH solution. > > "Warm the beaker gently by standing it in some hot water, stir until > all the oil dissolves in the alcohol and turns clear. Add 2 drops of > phenolphthalein solution. Using a graduated syringe, add 0.1% lye > solution drop by drop to the oil-alcohol-phenolphthalein solution, > stirring all the time, until the solution starts to turn pink and > stays that way for 10 seconds." ... > Biodiesel from waste oil > http://journeytoforever.org/biodiesel_make.html#biodwvo > > "Dissolve 1 gram of lye in 1 liter of distilled or de-ionized water > (0.1% w/v lye solution). In a smaller beaker, dissolve 1 ml of > dewatered WVO oil in 10 ml of pure isopropyl alcohol. Warm the beaker > gently by standing it in some hot water, stir until all the oil > dissolves in the alcohol and the mixture turns clear. Add 2 drops of > phenolphthalein solution. Using a graduated syringe, add the 0.1% lye > solution drop by drop to the oil-alcohol-phenolphthalein solution, > stirring all the time, until the solution stays pink (actually > magenta) for 10 seconds." ... > Basic titration > http://journeytoforever.org/biodiesel_make2.html#titrate > > "Instead of the usual 1 ml of oil and 10 ml of isopropyl alcohol, mix > 4 ml of oil in 40 ml of isopropyl alcohol in a glass beaker. Warm the > mixture gently by standing the beaker in hot water, stir until all > the oil disperses and it becomes a clear mixture. Then titrate as > usual, measuring milliliters of stock solution used." ... > Better titration > http://journeytoforever.org/biodiesel_make2.html#bettertitrate > > "Mix 10 milliliters of isopropyl alcohol in a small container with a > 1 milliliter sample of WVO -- make sure it's exactly 1 milliliter. > Take the WVO titration sample from the reaction vessel (Figure 5 #1) > after it's been warmed up and stirred. Add to this solution 2 drops > of phenolphthalein, an acid-base indicator that's colorless in acid > and red in base. Using a graduated eye dropper (with increments > marked in tenths of milliliters) or some other calibrated instrument > (from medical supply outlets), while carefully keeping track of the > amounts, drop measured amounts of the lye/water solution a couple of > tenths of milliliters at a time into the > WVO/isopropyl/phenolphthalein solution. Follow each drop with > vigorous stirring of the solution. In cold weather the WVO might > congeal and not work so you might need to do the titration in a > heated room. If conditions are right eventually the solution turns > pink (magenta), and stays pink for 10 seconds." ... > Mike Pelly's biodiesel method > Titration > http://journeytoforever.org/biodiesel_mike.html#titration > > >Any help would be appreciated. > > There's more info there about titration. You don't tell us just what > you did - did you use phenolphthalein or a pH meter? Spell it out, > step by step. > > Meanwhile I think you should give everything on these two pages a > thorough read: > > Make your own biodiesel > http://journeytoforever.org/biodiesel_make.html > > Three choices > 1. Mixing it > 2. Straight vegetable oil > 3. Biodiesel > Biodiesel > Where do I start? > What's next? > The process > Our first biodiesel > Biodiesel from new oil > Biodiesel from waste oil > Removing the water > Washing > Using biodiesel > Safety > How much methanol? > Ethyl esters -- making ethanol biodiesel > Reclaiming excess methanol > More about lye > How much lye to use? > Basic titration > Better titration > Accurate measurements > pH meters > Phenolphthalein > pH meters vs phenolphthalein > High FFA levels > Deacidifying WVO > No titration? > The basic lye quantity -- 3.5 grams? > Mixing the methoxide > Test batches > Stock methoxide solution > Poor man's titration > How much glycerine? Why isn't it solid? > PET bottle mixers > Viscosity testing > How the process works > What are Free Fatty Acids? > Iodine Values > -- High Iodine Values > -- Talking about the weather > Which method to use? > Why can't I start with the Foolproof method? > Quality > Quality testing > Cetane Numbers > National standards for biodiesel > -- standards and the homebrewer > -- standard testing > Biodiesel in gasoline engines > Home heating > Lamps and stoves > Other uses > Identifying plastics > > Best wishes > > Keith > > > > >Thanks > >Doug Memering > > > _______________________________________________ > 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/
