It will be very difficult to obtain a significant reduction in pollution from motor vehicles unless fuels are cleaned up. One key provision in the 1990 Clean Air Act was the requirement to reformulate gasoline sold in the smoggiest areas around the country. Reformulated gasoline (RFG) is gasoline that has been modified to reduce air pollution. It can be used in conventional engines with no modification. The composition of the gasoline is altered to reduce exhaust emissions and make them less photochemically reactive and toxic. RFG is not considered an alternative fuel, a gasohol, or an oxygenated fuel. The 1990 Amendments outline the requirements of RFG to be produced for use in ozone nonattainment areas.
The requirements include the following
- Conventional gasoline presently contains 32% benzene and its derivatives; reformulated gasoline must reduce this to no more than 25%. Benzene itself must be reduced to 1% by volume from as high as 5% in conventional gasoline.
- The oxygen content of reformulated gasoline must equal or exceed 2% by weight [ethanol and methyl tertiary-butyl ether (MtBE) are the primary oxygenates used].
- Reformulated gasoline will not have any heavy metals, and lead and phosphorus concentrations are limited to 0.05 and 0.005 gram per gallon, respectively.
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