Reprocessing or re-distilling or altering gasoline for long-term storage?

I have acquired 3 cars over the past year (fuel-injection, model years 2001 - 2004), I have a place to keep them and I'd like to keep a more-or-less full tank of gas in them but haven't driven them (much) and they might just sit for a year+ right now. A couple of years ago I ran a new gas line for a friend's 70's Massey Fergusen combine that had sit for maybe 6, 7 years but the fuel line clogged up. This summer after 10+ years I'm putzing with a 67 Dodge in storage (it has newer engine can run on unleaded) and it apparently had a small gas-tank leak, a very thick, tar-like puddle has formed under the tank, I assume this is what's left over that didn't evaporate after the more volatile components did. With both this Dodge and the combine, there was a very strong turpentine smell about them.

Bottom line is that I'd like to keep these seldom-used vehicles fueled up and not have to worry about the gas or have to drive them just to burn the gas up and not have to worry about the additives still working after 2, 3 or god knows how many years. Hence my questions about just what is it in retail pump gasoline that makes it turn to **** after 6 or 12 or 18 months and can I just get rid of it and end up with something stable and with enough octane (87 I guess). I'm not sure how, where or even if I can buy AV gas (Ontario, Canada). Marine gas (I assume contains no ethanol) is do-able.

I have no doubt that sooner than we're banking on that gas stations will disappear and non-farm / non-commercial gasoline will be hard to come by and I won't be the only one asking about long-term gasoline acquisition and storage.
 
What does the octane rating have to do with the long-term stability?

To answer your question some of the lighter fractions in gasoline will evaporate and some of the remainder can oxidize.
 
> What does the octane rating have to do with the long-term stability?

I was under the impression that some of the components in pump gas that causes long term storage problems is there to bring the octane up to the minimum 87 needed for most engines. If this is not true, then let me know.

> To answer your question some of the lighter fractions in gasoline will evaporate and some of the remainder can oxidize.

What exactly is in pump gas is there for reasons other than engine power generation (say, emissions modification, cleaning fuel injectors, etc) and is the reason that gas can't be stored in a closed air-tight container for more than, say, a year without going "bad". ?

I can store a lot of other petrochemicals (turpentine / varsol, acetone, laquer thinner, etc) for years and they seem to not change chemically.
 
> What does the octane rating have to do with the long-term stability?

I was under the impression that some of the components in pump gas that causes long term storage problems is there to bring the octane up to the minimum 87 needed for most engines. If this is not true, then let me know.

> To answer your question some of the lighter fractions in gasoline will evaporate and some of the remainder can oxidize.

What exactly is in pump gas is there for reasons other than engine power generation (say, emissions modification, cleaning fuel injectors, etc) and is the reason that gas can't be stored in a closed air-tight container for more than, say, a year without going "bad". ?

I can store a lot of other petrochemicals (turpentine / varsol, acetone, laquer thinner, etc) for years and they seem to not change chemically.
The octane rating is not connected to the storage longevity.

And for the rest I’m sure details can be found online. My minor in chemistry only takes me so far.
 
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leave 'em empty for long term storage (1 yr +). The hi
ETHO content w/modern ('07/8) gas (the "T" ran on it
w/gasoline as an option) helps it evap more.
Not sure on gas v other's storage beside that pumping
gas out a tank causes pressure (lack of) in there. It
is a tight system but not as tight asa cap on the other volitile chemicals U mention. More organic? Free radicals? THE Devil?
 
What exactly is in pump gas is there for reasons other than engine power generation (say, emissions modification, cleaning fuel injectors, etc) and is the reason that gas can't be stored in a closed air-tight container for more than, say, a year without going "bad". ?

I can store a lot of other petrochemicals (turpentine / varsol, acetone, laquer thinner, etc) for years and they seem to not change chemically.
Like I said before you can refine gas into its interim shelf stable chemicals, it just costs >$15/ gallon. More specific distillation is "sorting" and takes time and effort-- money.

They do put a little bit of stuff in for injector cleaning, fuel pump lubrication.

The stuff we get for $3 needs to be consumed at a reasonable pace because it's an unstable mix of crap. Including that goo you found on the floor after it evaporated, for example. I'd recommend looking at what VP racing fuels has in its catalog-- it will cost between pump gas and paint thinner.
 
...What exactly is in pump gas is there for reasons other than engine power generation (say, emissions modification, cleaning fuel injectors, etc) and is the reason that gas can't be stored in a closed air-tight container for more than, say, a year without going "bad". ?

I can store a lot of other petrochemicals (turpentine / varsol, acetone, laquer thinner, etc) for years and they seem to not change chemically...
Most of those petrochemicals are alone in metal cans and are not mixed with gasoline grade naphtha's. VOC's can 'diffuse' through plastic containers and leave oxidized naphtha.

The VOCs in US gasoline (about 15% by weight) can contain toluene, 2-methylbutane, p-,m-xylene, 1,2,4-trimethyl-benzene, n-butane, 2,2,4-trimethylpentane, 2-methylbutane, n-heptane, and cyclohexane, among others.
 
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> What does the octane rating have to do with the long-term stability?

I was under the impression that some of the components in pump gas that causes long term storage problems is there to bring the octane up to the minimum 87 needed for most engines. If this is not true, then let me know.

> To answer your question some of the lighter fractions in gasoline will evaporate and some of the remainder can oxidize.

What exactly is in pump gas is there for reasons other than engine power generation (say, emissions modification, cleaning fuel injectors, etc) and is the reason that gas can't be stored in a closed air-tight container for more than, say, a year without going "bad". ?

I can store a lot of other petrochemicals (turpentine / varsol, acetone, laquer thinner, etc) for years and they seem to not change chemically.
https://en.wikipedia.org/wiki/Gasoline
This Wikipedia article does have a decent overview of exactly what you are asking about.
 
I don't know if it's ever been suggested to create a sub-forum for gasoline (or fuel liquids generally) but it would seem natural for this website.

Anyways, I was wondering if it was possible to alter retail pump-gasoline to render it suitable for long-term storage (ie 1 or more years). I know there are fuel stabilizer additives, the performance of which I don't know (please comment if you know). I was thinking re-distillation might remove the unstable components? I guess I'm looking for some hard-core chemistry theory here. Also, maybe the possibility to start with marine or aviation gasoline? Perhaps they are naturally more suitable for long-term storage with less preparation?

(how about adding "stabilize" and "gasoline" as usable tags?)
I’m a head lab tech for a major oil company. We add antioxidants to gasoline so ours should store easy for one year of more as long as the container is sealed. We test every gasoline final tank for this. By artificially aging the fuel. No need to add any 3rd party additives. Marine gasoline is just a full octane gas with no ethanol. We make it for the Florida market. Don’t put AVGAS in an engine made for MOGAS. Also AVGAS is probably double the price.
 
I’m a head lab tech for a major oil company. We add antioxidants to gasoline so ours should store easy for one year of more as long as the container is sealed. We test every gasoline final tank for this. By artificially aging the fuel. No need to add any 3rd party additives. Marine gasoline is just a full octane gas with no ethanol. We make it for the Florida market. Don’t put AVGAS in an engine made for MOGAS. Also AVGAS is probably double the price.
Unfortunately that’s not true everywhere. Here the Milwaukee Marina only sells E10 which is the case in many EPA non-attainment areas.
 
Yes. It burns very hot as well. AVGAS has a lot of lead in it.
Burns very hot? Can you explain what you mean, is the flame temperature higher than with consumer gasoline?

And the lead content of 100LL is much less than was used in pump gas back in the 60s and early 70s but I agree it is not insignificant.
 
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"...too hi an octane, av gas etc..."
isn't it similar to detonation, pinging, timing advanced too far? the CC is way over heated,
firing offa lill imperfections in the cc, "melt down"?
 
"...too hi an octane, av gas etc..."
isn't it similar to detonation, pinging, timing advanced too far? the CC is way over heated,
firing offa lill imperfections in the cc, "melt down"?
A higher octane prevents pre-ignition, not causes it. And if the air/fuel mixture is detonating then that's a different problem and the engine will be destroyed.
 
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