What is MTBE and why is it being replaced?
MTBE is the chemical shorthand description for methyl tertiary-butyl ether. MTBE is another oxygenated hydrocarbon compound that has a high octane rating. It was initially a preferred compound widely used for octane enhancement as a replacement for leaded compounds in gasoline. When the EPA developed regulations requiring oxygenated gasoline to help reduce smog in several areas of the country, MTBE was the most commonly used compound to supply the additional oxygen, while ethanol was chosen for this purpose in the Midwest region of the country. Recently, most states have banned the use of MTBE because of its tendency to work its way into ground water systems, usually from leaks and spills, as an undesirable contaminant. Ethanol is being used as a replacement.