>Benzene occurs naturally as a component in petroleum and natural gas condensate.
Roger.
>Interestingly, benzene is still allowed to be mixed into gasoline for improved performance.
Negatore.
Since the 1990's it has *no longer been allowed* beyond the levels cited in the article. It is almost never added to gasoline intentionally, rather the fuel blending components are combined to reduce the benzene content from the typical 5% levels that were common up until then.
Going back a bit further, in the early Model T days before leaded gasoline, benzene was known as benzol and was available as a premium alternative to regular gasoline. They called benzene Hi-Test and when leaded gasoline came along that was then widely known as "Ethyl" after the company that made the tetraethyllead additive. Benzene was only about 90% pure back then so it did not freeze solid as high as 5 degrees C in the fuel tank like 99.9% material would do at modern purity levels.
Regardless, at about a 100 octane antiknock rating, benzene is what internal combustion engines are designed to run on under ideal conditions.
Interestingly cyclohexane, which has the same hexagonal 6-carbon structure as benzene but with 6 additional hydrogen atoms around the circle, has a miserable antiknock performance.
Roger.
>Interestingly, benzene is still allowed to be mixed into gasoline for improved performance.
Negatore.
Since the 1990's it has *no longer been allowed* beyond the levels cited in the article. It is almost never added to gasoline intentionally, rather the fuel blending components are combined to reduce the benzene content from the typical 5% levels that were common up until then.
Going back a bit further, in the early Model T days before leaded gasoline, benzene was known as benzol and was available as a premium alternative to regular gasoline. They called benzene Hi-Test and when leaded gasoline came along that was then widely known as "Ethyl" after the company that made the tetraethyllead additive. Benzene was only about 90% pure back then so it did not freeze solid as high as 5 degrees C in the fuel tank like 99.9% material would do at modern purity levels.
Regardless, at about a 100 octane antiknock rating, benzene is what internal combustion engines are designed to run on under ideal conditions.
Interestingly cyclohexane, which has the same hexagonal 6-carbon structure as benzene but with 6 additional hydrogen atoms around the circle, has a miserable antiknock performance.