Reformulation of gasoline

In the U.S. the 1991 Clean Air Act Amendment will require the reformulation of gasoline in CO and ozone non-attainment areas. A number of areas that are currently not non-attainment will also have the right to opt for reformulated gasoline. Estimates of the volume of gasoline affected vary, but a likely scenario is that about half of the gasoline sold in the U.S. could be reformulated in the 1990 s. The drive for reformulated gasoline is to reduce CO, NO, and hydrocarbon emissions. 

Predicting catalyst developments is outside the scope of this paper, but expect many of those improvements to be related to environmental issues. Commercialization of catalysts like Davison s RFG-1 will be required to meet the challenges of the probable worldwide reformulation of gasoline. SO reducing additives are already available, but there is as yet no commercially available FCC additive to reduce NO emissions. Because of greenhouse effect concerns, there may even be the need for a catalyst to achieve high FCC conversions at ultra-low coke makes. 

The elimination of lead, the reduction of aromatics in gasoline, and the desulfurization of diesel fuels are oing to require significant reformulations of these products that will irripiy development of specific additives that allow the refiner to optimize costs while meeting the required specifications. 

By selection of appropriate operating conditions, the proportion of coproduced methanol and dimethyl ether can be varied over a wide range. The process is attractive as a method to enhance production of Hquid fuel from CO-rich synthesis gas. Dimethyl ether potentially can be used as a starting material for oxygenated hydrocarbons such as methyl acetate and higher ethers suitable for use in reformulated gasoline. Also, dimethyl ether is an intermediate in the Mobil MTG process for production of gasoline from methanol. 

G. J. den Otter, R. E. Malpas, and T. D. B. Morgan, Effect of Gasoline Reformulation on Exhaust Emissions in Current European Vehicles, SAE 930372, Society of Automotive Engineers, Warrendale, Pa., 1993. 

The other large-scale ethanol user is the USA, where ethanol has been used to increase the octane rating of gasoline, to decrease carbon monoxide emissions, and, more recently, to replace MTBE (methyl tert-butyl ether) in reformulated gasoline. Ethanol production in the USA grew from about 0.6 billion liters in 1980 to... 

The reduction in the lead content of gasoline and the introduction of reformulated gasoline have been very successful in reducing automobile emissions, due to changes in gasoline composition, with further improvements in fuel quality proposed for the early decades of this new millennium. These projections are accompanied by a noticeable and measurable decrease in crude oil quality, and the reformulated gasoline will help meet environmental regulations for emissions for liquid fuels but will be subject to continuous review because of the potential for environmental impact. 

Source In exhaust of gasoline-powered engines (1.8 vol % of total exhaust hydrocarbons) (quoted, Verschueren, 1983). Detected in California Phase 11 reformulated gasoline at a concentration of 170 mg/kg (Schauer et al, 2002). 

The world energy crisis of the 1970s, however, spurred interest once again in ethanol as a transportation fuel source. Brazil adopted the widespread production and use of Alcool, hydrated ethanol, and Gasolina a 78 22 ratio blend of gasoline ethanol as a motor fuel. Other countries developed policies to maintain a fuel grade ethanol industry by conversion of biomass. Also, clean air and reformulated fuel policies have helped to promote the use of ethanol as a viable alternative fuel. 

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