Which fuel is better?

[sbw1]

The way I understood it, ethanol is the new octane improver. It replaces MTBE (the old octane improver). I took that to mean if you get "non ethanol" gas, it still is the old stuff - with MTBE. Is that not correct?

No. I don't believe it is. Refineries used to be protected from lawsuits by federal law when adding the MTBE to get the octane boost. Once the stuff started to show up in ground water monitoring wells, the law was changed and they stopped adding it. I'm not sure how they get the octance boost today (other than ETOH) but someone will probably chime in.

 

[Lazy Daze]

No. I don't believe it is. Refineries used to be protected from lawsuits by federal law when adding the MTBE to get the octane boost. Once the stuff started to show up in ground water monitoring wells, the law was changed and they stopped adding it. I'm not sure how they get the octance boost today (other than ETOH) but someone will probably chime in.

Interesting. I wasn't aware that they had to stop using MTBE. I thought it was only strongly suggested - or something like that. I'll be curious to know the final result. Thanks.

 

[sbw1]

Interesting. I wasn't aware that they had to stop using MTBE. I thought it was only strongly suggested - or something like that. I'll be curious to know the final result. Thanks.

I think you are correct. They did not have to stop, but the threat of lawsuits was the strong suggestion that caused the change.

 

[Lazy Daze]

the threat of lawsuits

Unfortunately, that's usually what it takes for companies to change.

 

[JeffM]

The primary reason for adding either MTBE or ethanol is to add oxygen to the combustion process, reducing emissions.