Emission methanol fuel vehicles

In the late 1980s attempts were made in California to shift fuel use to methanol in order to capture the air quaHty benefits of the reduced photochemical reactivity of the emissions from methanol-fueled vehicles. Proposed legislation would mandate that some fraction of the sales of each vehicle manufacturer be capable of using methanol, and that fuel suppHers ensure that methanol was used in these vehicles. The legislation became a study of the California Advisory Board on Air QuaHty and Fuels. The report of the study recommended a broader approach to fuel quaHty and fuel choice that would define environmental objectives and allow the marketplace to determine which vehicle and fuel technologies were adequate to meet environmental objectives at lowest cost and maximum value to consumers. The report directed the California ARB to develop a regulatory approach that would preserve environmental objectives by using emissions standards that reflected the best potential of the cleanest fuels. 

K. H. Heilman, G. K. Piotrowski, and R. M. Schaefer, Start Catalyst Systems Employing Heated Catalyst Technology for Control of Emissions from Methanol-Fueled Vehicles, SAE 93082, Society of Automotive Engineers, Warrendale, Pa., 1993. 

Methanol also seems to biodegrade quickly when spilled and it dissolves and dilutes rapidly in water. It has been recommended as an alternative fuel by the EPA and the DOE, partly because of reduced urban air pollutant emissions compared to gasoline. Most methanol-fueled vehicles use a blend of 85% methanol and 15% gasoline called M85. Building a methanol infrastructure would not be as difficult as converting to hydrogen. While methanol can be produced from natural gas, it can also be distilled from coal or even biomass. In the 1980s, methanol was popular for a brief time as an internal-combustion fuel and President Bush even discussed this in a 1989 speech. 

Finlayson-Pitts, B. J., J. N. Pitts, Jr., and A. C. Lloyd, Comment on A Study of the Stability of Methanol-Fueled Vehicle Emissions in Tedlar Bags, Environ. Sci. Technol., 26, 1668-1670(1992). 

Methanol also seems to biodegrade quickly when spilled and it dissolves and dilutes rapidly in water. It has been recommended as an alternative fuel by the EPA and the DOE, partly because of reduced urban air pollutant emissions compared to gasoline. Most methanol-fueled vehicles use a blend of 85% methanol and 15% gasoline called M85. 

Fig. 2. CEC methanol-fueled vehicle exhaust profile for (a) HC, hydrocarbons (b) NO and (c) CO. Solid line represents State of California standard maximum emissions. Methanol HC emissions are calculated as CH g5 and not corrected for flame-ionization detector response.

Andino, J. M. and Butler, J. W., A study of the stability of methanol-fueled vehicle emissions in Tedlar bags. Environ. Sci. TechnoL, 25, 1644-1646, 1991. 

Engines are also designed to use either gasoline or methanol and any mixture thereof (132—136). Such a system utilizes the same fuel storage system, and is called a flexible fueled vehicle (EEV). The closed loop oxygen sensor and TWC catalyst system is perfect for the flexible fueled vehicle. Optimal emissions control requires a fuel sensor to detect the ratio of each fuel being metered at any time and to correct total fuel flow. 

Compared with other alternative motor fuel options (reformulated gasoline, compressed or liquefied natural gas, ethanol from corn or coal, methanol and electricity), propane has the lowest greenhouse gas emissions except for natural gas. According to a 1998 study by the Institute of Transportation Studies, greenhouse emissions from propane vehicles arc 21.8 percent less than from gasoline or diesel. 

Dunker, A. M Relative Reactivity of Emissions from Methanol-Fueled and Gasoline-Fueled Vehicles in Forming Ozone, Environ. Sci. Technol., 24, 853-862 (1990). 

Vehicle tests to evaluate the performance, emissions, and fuel economy of methanol/gasoline blends in current and near-future vehicles. 

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