I have a couple of questions about this. I understand one of the biggest issues with WVO is gelling. What causes it to gel? How much (if any) of the gelling problem is due to water in the oil? Will anti-gel additives for diesel fuel help - or prevent - the problem?

I know that heating the veg-oil and starting/shutting down the engine on diesel are common solutions to the viscosity issues, but I'm trying to learn more. I was wondering about how much benefit there would be to "cooking" the water out of the oil - maybe using vacuum to lower the boiling point so that the water would boil out at a lower temp....

 

No water is not the issue. Hydrogenated oils are one of the problems. At normal temperatures they are solid. If your source of WVO is using partial Hydrogenated oil you will have some solid oil in you WVO. Heat is the only why to melt the solid oil.

 

You're sure hydrogenated oils don't contain water? I thought that is what made them hydrogenated.

Soft margarines for example are almost totally hydrogenated oil (plus a little coloring, salt, flavoring, and preservatives). Heat a glop of it in the microwave and pour the oil layer off the top and what do you have left? WATER!

If what you're saying is right (and I'm not saying it isn't - I don't know - that's why I'm asking all the dumb questions) then pure vegtable oil wouldn't gel any worse than dino juice, because it wouldn't have any hydrogenated oil in it. Is that the case?

Maybe I'm misunderstanding the term here. Gonna' have to do some research on what exactly hydrogenated oil is....

 

I have no opinion but here is what I've seen in my garage over the last 17 months of running WVO

If I hot pan test a sample of oil and I get very few bubbles (very subjective) but say less then 100 or 200 from the foam cup full I test, I'm happy.

In the winter some of my oil has jelly in it. As I dump it in my tank I see this go buy. This is when the temps are in the 40F range.

My heated system and filter don't seem to mind this jelly, I assume if they did my filter life would be short in the winter. It is not, I get well over 4-5K miles out of my WVO filters year round.

All my oil comes from two sources. My brother-in-laws resturants. He dumps the oil back in the cubes for me and delivers to me. No water other then what ever may happen in the frying process gets in the oil I use.

Conclude what you want from this. I'm not sure what it all means but my truck is running perfectly today as it did the day I converted it at 3900 miles.

Erick
2005 F250 PSD
Plant Drive Two tank WVO system.
Hotstk, Vormax, A1000 and Vegtherm

 

Eric,

Do you know if the oil your are using Hydrogenated?

 

It is not Hydrogenated. It's pure salid oil from Soy Bean.

As for what they cook in it. Can't say. He's never real clear on it's use. It a chines resturant and some of the oil comes to me in almost perfect shape and some of it comes to me thick and yellow.

Here is a pic of three differant cubes I have in the garage right now unfiltered. All the cubes came from the same resturant.




The left one is really nice and I often ask myself why I'm even filtering it before I use it in my truck.

The Middle one is something that will have to wait till this summer to use. So i have no idea what was cooked in it to get it in this shape. I think for the fun of it I'll do a hot pan test on some of the oil in the middle cube this weekend.

The far right is a cube of "bottoms of other cubes" as I get to the bottom of a cube I dump it in this cube. When it gets full I suck the good oil off the top and the bottom is trash .

Erick

 

Well, I did a little 'net research and found out that my concept for hydrogenation was all wrong. I always assumed (dangerous word) that water (hydro) was being emulsified into the oil to hydrogenate it. Totally wrong.

To hydrogenate oil they heat it and then bubble hydrogen gas through it! Now, I don't even want to think about the fire/explosion potential of hydrogen gas combined with heat and flammable oil....but anyway, that is how they do it. The process actually results in additional hydrogen atoms attaching themselves to the carbon atoms of the fatty-acid molecules in the oil, making it a semi-solid (e.g. Crisco, margarine, etc.) hydrogenated oil.

Apparently That's the reason for using methanol and lye in the biodiesel brewing process. The reaction strips the small hydrogen/carbon groups off of the glycerol "backbone" of the larger fatty-acid molecule chains. These small hydrocen/carbon groups, once freed from the long fatty-acid molecule chains, forms the thinner ester oil that is biodiesel.

Facinating stuff....

 

leskwvo,
I get my oil from a friends resturant, he dumps the oil into my 55 gal drum. When its cold the oil looks like your middle cube as soon as I heat it in my heating drum it turns back to the nice dark brown oil. The only problem is pumping it out of the drum when it's real cold ( in the low 20s & teens). If I get there when hes changing the oil the hot oil he dumps in will reliquify the whole drum. I made a heater out of a hotwater heater element and some black pipe it works great for cold weather pickup. I've made alot of batches of Bio and so far no difference. I know he uses the same oil all the time, its called a soybean shorting.

 

Yeah that is why I just sit these aside and wait till summer as I said. I get plenty of the stuff on the left so don't need ther solid ones this time of year.

Erick

 

Jeeper

If you are up for a little Organic Chemistry I will try to explain this to you.

I might get a little to basic for you but that's because I dont know where you stand in knowledge of atomic structure. Additionally, there are some basic facts that you'll have to accept as true because there isn't enough room here to post a textbook on Quantum Mechanics.

1. the Atom is the smallest unit any substance can be divided into. While it is made up of subatomic particles (protons, electrons, and neutrons) if you remove any of these particles you alter the nature of the atom so it becomes something else. Groups of identical atoms form an element.

2. Atoms consist of a nucleus containing protons and an equal number of orbiting electrons. The Nucleus may also contain neutrons but they are not important here.

3. Adding another proton and electron forms a new element ( 1 proton and 1 electron is hydrogen, 2 protons and 2 electrons is Helium, 3 protons and 3 electrons is Lithium, and so on)

4. Each electron is in a specific orbit and each orbit can hold 2 electrons (a pair) they are 180 degrees apart (on oposite sides of the nuculeus)

5. The electron orbits are assigned to energy shells with each shell being a little farther away from the nucleus than the preceding shell.

6. The farther away from the nucleus an energy shell is located the more orbits it contains. (the first shell has 1 orbit and holds 2 electrons, the second shell has 4 orbits and holds 8 electrons, the third shell has 9 orbits and holds 18 electrons, etc.)

7. As the number of electrons increases they are added in a specific sequence.
a. Each orbit in an energy shell must contain an electron before the second electron is added to any orbit.
b. All orbits in an energy shell must be full, contain an electron pair, before any electrons are placed in higher energy shell orbits.

8. Atoms bond to other atoms by sharing electrons with each other (this is true for covalent bonds and that is the type of bond we are concerned with here, there is another type of bond called ionic bonding in which one atom actually steals one or more electron from another atom but ionic bonding plays very little part in organic chemistry)
a. Only electrons in the outer energy shell can be shared.
b. Only unpaired electrons will be used for sharing (bonding).
c. By sharing electrons with each other atoms are able to fill their individual outer shells with paired electrons without violating the equal number of protons and electrons rule. (this is a very stable state for the atoms)
d. An atom can and will form as many bonds as it has unpaired electrons.

Ok thats the basics now lets explain hydrogenation

Carbon has 4 unpaired electrons in its' outer shell, one in each of 4 orbits so it forms 4 bonds. 1 Carbon bonded to 4 Hydrogen = CH4 = Methane.
Carbon often fills one of the bonds by bonding to another Carbon each carbon may then bond to 3 Hydrogens that = CH3-CH3 or C2H6 = ethane add another carbon and we are building a carbon chain it is 3 carbons bonded in a straight line with the end carbons each also bonded to 3 Hydrogens and the center carbon bonded to 2 Hydrogens it looks like CH3-CH2-CH3 or C3H8 thats propane the pattern repeats as you build a longer carbon chain so CH3-CH2-CH2-CH3 or C4H10 is next that is butane. You can see why they are called hydrocarbons.

As long as this pattern continues carbon bonded to carbon in a straight line with each end carbon bonded to 3 hydrogens and another carbon and the internal carbons bonded to 2 carbons and 2 hydrogens the chain is said to be saturated.

Occasionally 2 adjacent carbons will actually share 2 pairs of electrons instead of 1 pair as in the examples above and are said to be double bonded. When that happens those carbons cannot bond to as many hydrogens, remember only 4 bonds per carbon atom. the simplest example of this is 2 carbon atoms double bonded and each carbon is bonded to 2 hydrogens that is CH2=CH2 or C2H4 ethene (note the slight spelling difference.) You can of course have CH3-CH2-CH=CH-CH3 pentene and etc.

Hydrocarbon chains that contain double bonds are said to be unsaturated.

Hydrogenation is the process of converting an unsaturated hydrocarbon to a saturated hydrocarbon by breaking one of the two bonds in the double bond and filling it with hydrogen thus Hydrogen - ation.


Not quite
The hydrocarbon groups striped off of the glycerin backbone are actually quite long, 10 to 15 carbons, and they are the fatty acids that are esterified to form Biodiesel. The glycerin backbone is only 3 carbons long. Each VO molecule consists of a glycerin backbone with 3 of those fatty acids attached to it. the glycerin gets the OH from the Methanol (MeOH) to form the trialcohol glycerol and the fatty acids are esterified with the Me from the ethanol to form the alkyl esters that make up Biodiesel.

 

Phydeaux88

I feel like I just got a few collage credits reading your post below. Thanks

Erick

 

Phydeaux88, thanks for going o all the trouble to type all that. Good refresher. I'm an engineer so I took a full year of chem in college - loved it BTW. Though we didn't do much with organic chem. I already knew the basics (items 1-8), but like I said, good refresher.

I read the info on hydrogenation on Wikipedia. Naturally they didn't get as technical or detailed as your post, though they mentioned the glycerine "backbone" of the molecules. My statement about the reason for using methanol and lye in brewing bio was my own inference from what I already knew about bio and what I read about hydrogenation. The details on the part the MeOH plays in the reaction was the main new (for me) info you supplied in your post. Again, facinating stuff.

I'd infer from all you've said that the lye acts as a catalyst to enable the MeOH and VO to react and separate into the fatty acid esters and glycerol?

 

You've got that about right, jeeper, but I personally do not use any hydrogenated oils. Just because they are easier to work with. Its hard to pump from a 55 gal drum of cold hydrogenated oils behind a restaraunt, however if they use non hydrogenated it is no big deal at all. Its not that hard to find as you would think.

 

CJ
sorry if I got to basic for you but I had no idea what your level knowledge on the subject was. Since understanding basic atomic structure is esential to understanding covalent bonds and why Carbon forms four bonds.

You got it!!