Preserving fuel with CO2?

[SecondMonkey]

I got one of those little CO2 regulators from Lowes that works on a 20oz paintball type tank, to power small air tools. I was thinking, what if I purged any air in a gasoline container with CO2? Isn't the main purpose of fuel stabilizers to form a layer on top of the fuel and prevent contact with oxygen? Would filling the air space with an inert gas have a similar effect?

Or to put it another way, what makes fuel "go bad" exactly, and what does Stabil do that's supposed to stop that?

 

[mechanicx]

The way I understand it is Sta-bil prevents oxidation of the fuel. I'm not sure if it creates an oxygen proof top layer or if actually lighlty bonds throughout to the fuel to prevent oxidation. Sta-bil also states it contains cleaners and lubrication.

The problem with C02 is it contains O2. I'm not sure that the 02 is available for oxidation though. I'd think Nitrogen would be better. And you would need something heavier than air.

As always you should keep your fuel tanks as filled as possible during storage to prevent any excess air contact.

 

[labman]

A CO2 blanket is a common technique in the chemical industry. When I worked in the Labs at Rinshed Mason and Ashland Chemical, we always had cylinders of CO2 to pipe it into our flasks. When working with urethanes, we used the less reactive nitrogen. The plant used burned air.

We used a continuous flow, but a blanket would help. I think Stabil has anti oxidents to prevent polymerization, gum formation.

Run the exhaust into the tank before shutting down?

 

[Boomer]

Chemicals like Stabil provide a sacrificial antioxidant, usually a hindered phenol. In the presence of oxygen, the phenolic is preferentially oxidized to a quinone. This protects the fuel from reacting with oxygen UNTIL THE SACRIFICIAL COMPOUND IS CONSUMED. CO2 is not really capable of carrying out oxidation and is an inert gas so, yes, it would protect fuel from being oxidized provided that it did not slowly leak out and be repalced with air containing oxygen. However, CO2 is capable of reacting with various reagentslike strong base. so as Labman suggests, nitrogen is better and argon is the best of all.