Oxidisation/Polymerisation on Cottonseed oil - photos

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

I went out to have a look at the few tins I have left but the ones I have held on to are the cleaner ones or have the plastic thread inserts and lids and none of them have have the goo. I might try putting some oil around the lids of a few and seeing if I can re create the effect.

Tony,
Where would a person actually send this stuff to be anylised and what would they ask? Would the lab need some specification of what you are looking for over a " What is it?" request?
What is your ballpark estimate of what such a test would cost?

I suggest that a Tertiary institution which has chemical courses, especially one which has renewable fuels / energy courses may be a good place to start.
I do not have costs for testing.
I do not know what tests are needed to identify the substance, but not having any tests done at all, and to keep asking "what is it" will not get a definitive answer.
I did suggest some simple tests to determine whether it is soluble, flamamable, etc. These tests could be done at no cost.
Tony

[hannahs bridge Donating Member Find all posts View Profile Close hannahs bridge]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

To test for oxidation it is necessary to conduct a Peroxide Test, as pointed out in the article eluded to at the beginning of this thread.
SGS at Toowoomba (0746330599) will do this for $66.

Malcolm.

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

Members,
The Treasurer of WARFA has contacts in the oilseed industry and will seek to have them identify the substance. Initial observations are that the substance has darkened since removal from the tank, it has a cohesive, putty like consistency, which it has been suggested indicates a greater potential of the cause being fungal rather than microbial.

We will wait for the report on the substance's properties and composition with bated breath.

Discussions also raised the likelihoood of an "infection" in the fuel tank which should be "disinfected" to prevent a recurrence. This should be done in any diesel fuel bioligical or fungal contamination as the smallest leftovers will most likely reinfect the fuel system.

Regards,
Tony

[W123 x 2 Senior Member Find all posts View Profile Close W123 x 2]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

If someone will send me a sample, I will get it analysed at a govt. lab (no charge). PM me for contact details etc.

Michael

[BrianW Senior Member Find all posts View Profile Close BrianW]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

A few of points

1. The tank was first used for vege oil.
2. The first lots of my oil had been sitting for many months in drums on the side of my house. I only used the top portion
3. The formation of the material was seen very early on.
4. The was no rust inside the tank. It was perfectly clean and it seemed that the steel had been etched so was participating in the reaction.
5. Tests at a lab indicated starch was present as well as iron - the conclusion by the very interested owner of the facility was that the iron was acting as a catalyst in the reaction. I am sure this was with the peroxide test.
6. The iron acting as a catalyst was also suggested in the above mentioned report and therefore fitted what I had found so far. Based on this I painted the inside of the tank to remove the catalyst.

The only part of the advice that was ignored was that I should be filtering and running blends to fix the problem. This is a great preventative measure, but so is running 100% diesel. I got my original advice from a company in Canada, who suggesting using the VORMAX and I have been trying to achieve the goal ever since. It is using the two tank system and switching to 100% WVO once warmed up.

The formation of the material in my tank is another obstacle and I want to find the solution, which at the moment is a painted tank (internally). I suspect that the addition of a small amount of antioxidant would give me the same result and if a mL will fix the problem then it is a cheap option.

I tend to agree that the addition of ULP would allow vapour to be present in the top part of the tank, but this would not have been the reason I might have run the ULP in the first place - just a side effect. Of course the use of the wrong type of additive would also have a negative effect.

My thanks to those showing interest, asking question and offering advice (including yours Tony).

regards
Brian

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

Brian,
You are welcome. If I can be of assistance. please feel free to ask.

I am happy that painting the innards of the tank has solved the immediate problem.

As I have said, I also have a mild steel tank, but have no inidcation that this is occurring in there. I will keep an eye on it and report if I find any evidence of polymerisation of the oil.

Regards,
Tony

[Fitian Was here Find all posts View Profile Close Fitian]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

As you all know I have been using my main tank "mild steel" for vegy oil since October and had no signs of such problems too.

[TroyH Senior Member Find all posts View Profile Close TroyH]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

Something I hadn't really considered until just now, is that if you are running WVO, you don't just have vegetable oil in your tank, you have a cocktail of carboxylic acids in there also, which potentially could react with your tank, being metallic. It would likely react much faster with things like copper and zinc.
So perhaps it isn't acting as a catalyst at all, but is being oxidised by the acid in the oil.

I will have a look at corrosion data for mild steel in a few carboxylic acids (if I can find it) and see.

[Tim-HJ61 Donating Member Find all posts View Profile Close Tim-HJ61]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

Folks,

All will be revealed soon - I hope. Three samples have been given to others for lab analysis - let's hope they all come back with consistent results!!!

Tim

[bruceT Senior Member Find all posts View Profile Close bruceT]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

Tim, what your mate has in his tank is simply an oxidation reaction. Our veg oils are basically fatty acids which can oxidise in the presence of oxygen and water. Simply put, this is a reaction in which Oxygen attacks an unsaturated fatty acid at the Carbon molecule immediately adjacent to an unsaturated site in the molecular chain.

There can be a number of causes for this reaction. To summarise the Frybrid article, they are:

1. Availability of Oxygen- fuel storage tanks provide an ample supply of oxygen for the reaction.

2. Heat- A rule of thumb in chemistry is that the rate of a reaction doubles with every 10 deg C increase in temperature.

3. Presence of Pro-Oxidants. Some Pro-Oxidants found in Veg Oil systems are Copper, Mild Steel, Zinc, and Aluminium.

4. Light- Ultraviolet light can act as a pro-oxidant.

5. Time- Longer exposures increase the degree of oxidation.

Now, tying all of these reactions together, free fatty acids, even though only sparingly soluble, are carried in any water present and can therefore attack any metals they encounter. These metal ions can then catalyse the oxidation reaction. Given enough oxygen, enough heat, the right metal catalyst, this oxidation can be quite rapid.

The problem with this rapid oxidation in vegetable oils is that the peroxide free radicals produced can and do also react with unsaturated sites to form long chain, cross-linked polymers, con verting a triglyceride with a molecular weight in the 100’s to a polymer with a molecular weight in the millions. The effect of these polymers can range from the major inconvenience of tank fouling!

If you use a metal tank for holding Veg oil, it should be coated with something like a good epoxy. POR15 would be the best one for this job.

For this reason I don’t use my main fuel tank for holding veg oil and is one reason for preferring the plastic fuel tanks.

By the way, oils with lower iodine values have better oxidative stability than oils with high iodine values.

Hope this helps….

[Fitian Was here Find all posts View Profile Close Fitian]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

Hello Bruce,

It is great to have you back on the forum. Loaded with useful info.

I have actually been using the main tank in the merc for vegy. It's been over 5 months now. Yet I have no such dramas and the CAV filter never gets any of that too. The tank is not heated and the return line is not heated too. Do you think it will still happen sooner or later?

Thanks

[bruceT Senior Member Find all posts View Profile Close bruceT]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

Hi Fitian

Not necessarily. If you use up your fuel quickly and are therefore turning over your fuel storage in a short time, then you are reducing the risk. Remember "time" is one of the factors with oxidation. With temperature being a factor too, heated metal fuel tanks are at risk too, but your 300D tanks are not heated. It would also be safe to presume that most metal fuel tanks on older vehicles have corroded internally and would have metal parts in contact with the fuel, plus a bit of H2O, so increasing the risk. Cleaning this stuff out, if it happened would be no picnic, so check the screen filter periodically for signs of any build-up.

Yes, I'm busy catching up on all the threads which are most interesting. I see you've been quite busy and have done some really good work with your cars. Excellent photos too.

[Urvey Member Find all posts View Profile Close Urvey]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

I don't know if this is the correct place to post this, but what is this crusty layer in my filtering/heating barrel? The oil shown in the photo has been sitting in the bottom of my painted steel drum for about 2 months. When I run my finger through it, it lookes like an icebreaker going through ice. I've had the same layer forming on some of my unfiltered oil but only the stuff which has been sitting there for over a week. I've since filtered out the layer and used the oil (I was desperate) so I cant run any more experiments on it. It was particularly cold in Adelaide when I noticed this (14*C) so I was thinking that maybe it was a layer of solidifyed oil, but why did it not happen to the newish oil?

Any ideas?

Bryan

[bruceT Senior Member Find all posts View Profile Close bruceT]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

I don't know if this is the correct place to post this, but what is this crusty layer in my filtering/heating barrel? The oil shown in the photo has been sitting in the bottom of my painted steel drum for about 2 months. When I run my finger through it, it lookes like an icebreaker going through ice. I've had the same layer forming on some of my unfiltered oil but only the stuff which has been sitting there for over a week. I've since filtered out the layer and used the oil (I was desperate) so I cant run any more experiments on it. It was particularly cold in Adelaide when I noticed this (14*C) so I was thinking that maybe it was a layer of solidifyed oil, but why did it not happen to the newish oil?

Any ideas?

Bryan

Looks like wax to me Bryan. However if your oil is from a fish n chip shop, it could also be palm oil or some similar HMP oil that some foods are pre-fried in at the factory and which then mixes with whatever veg oil the shop uses. Cold filtering will remove it.

[Captain Echidna Senior Member Find all posts View Profile Close Captain Echidna]

Re: Oxidisation/Polymerisation on Cottonseed oil - photos

I have often seen it floating and have just not put it into the car, I believe its wax. Only a problem if you heat your oil to filter it, as it will reform when it gets colder. Or your filter will catch it all before it gets to the engine. As Bruce says, cold filtering will catch it.
From my expirence high melt point oils/ fats sink to the bottom.