Methanol/gasoline mixtures

The tendency to separate is expressed most often by the cloud point, the temperature at which the fuei-alcohol mixture loses its clarity, the first symptom of insolubility. Figure 5.17 gives an example of how the cloud-point temperature changes with the water content for different mixtures of gasoline and methanol. It appears that for a total water content of 500 ppm, that which can be easily observed considering the hydroscopic character of methanol, instability arrives when the temperature approaches 0°C. This situation is unacceptable and is the reason that incorporating methanol in a fuel implies that it be accompanied by a cosolvent. One of the most effective in this domain is tertiary butyl alcohol, TBA. Thus a mixture of 3% methanol and 2% TBA has been used for several years in Germany without noticeable incident. 

J. V. D. Weide and R. J. Wineland, "Vehicle Operation with Variable Methanol/Gasoline Mixtures," 6th Int. Symp. on Alcohol Euels Technology (Ottawa, Canada, May 21—25, 1984), Vol. 3. 

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. 

The illustrated unit can be used to study vapor-phase reforming of kerosene fractions to high octane gasoline, or hydrogenation of benzene, neat or in gasoline mixtures to cyclohexane and methylcyclopentane. In liquid phase experiments hydrotreating of distillate fractions can be studied. The so-called Solvent Methanol Process was studied in the liquid phase, where the liquid feed was a solvent only, a white oil fraction. 

A mixture of H2 and CO is an important chemical intermediate as are pure H2 and pure CO, and this mixture is called syngas or synthesis gas. These intermediates are used for production of gasoline, ammonia, methanol, and acetic acid. 

These considerations are particularly important in the area of alternative automotive fuel combustion. Methanol/gasoline mixtures are now recognized as an important alternate fuel candidate for use in conventional engines as well as for future automobile power plants (3). Large scale experiments are being conducted in Germany and the U.S., and... 

Index of Refraction Measurements. The use of Index of refraction measurements to study variations In concentrations of alcohol/ gasoline mixtures, during swelling or after equilibrium swell, was attempted. For calibration, the Indices of refraction of several ethanol/lndolene HO-III and methanol/Indolene HO-III mixtures were... 

Aromatics, MTBE, Olefins, T90 RVP, Ethanol, ETBE, MTBE Methanol/Gasoline Mixtures Sulfur... 

Reid vapor pressure of methanol/gasoline mixtures. 

In a conventional gasoline containing hydrocarbons or even ethers, the presence of water is not a problem in fact, water is totally soluble up to about 50 ppm at ambient temperature. Beyond this value water separates without affecting the hydrocarbon phase and the water leg can be withdrawn if necessary. On the other hand, in the presence of alcohols (ethanol and especially methanol), trace amounts of water can cause a separation of two phases one is a mixture of water and alcohol, the other of hydrocarbons (Cox, 1979). 

Fig. 5. Emissions from a GM Corsica VFV for gasoline and gasoline—methanol mixtures where represents total organic material, including hydrocarbons, methanol, and formaldehyde U represents NO formaldehyde and Hcarbon monoxide.

In Germany in the early 1950s, a 50 50 mixture of methanol and 2-propanol was blended with gasoline, first at a level of 7.5% and later at 1.5% (79). Complaints about stalling, power loss, and phase separation caused the ratio to be changed to 60 40 methanol 2-propanol but this apparentiy aggravated... 

The most extensive worldwide program on methanol blend gasoline was in Italy where from 1982 to 1987 a 1.9 x lO" m /yr (5 x 10 gal/yr) plant produced a mixture containing 69% methanol. The balance contained higher alcohols. This mixture was blended into gasoline at the 4.3% level and marketed successfully as a premium gasoline known as Super E (82). 

Initially, at least, methanol vehicles should be capable of operating on either M85, gasoline, or any mixture of the two. These vehicles are caHed flexible fueled (EEV) or variable fueled vehicles (VEV). It is expected that methanol could be sold in existing service stations out of tanks constmcted of methanol-tolerant material such as carbon steel or certain fiber glass formulations. EventuaHy, if enough EEV/VEVs are sold and methanol becomes widely avaHable, dedicated vehicles would likely be buHt and sold. Methanol has been used for years as a racing fuel. 

SO as to end the air mixture to adsorber No. 2. The system is then fully automatic. Solvents which have been successfully recovered by the activated carbon adsorption method include methanol, ethanol, butanol, chlorinated hydrocarbons including perchlorethylene, which boils at 121 C (250 °F), ethyl ether, isopropyl ether, the acetates up to amyl acetate, benzene, toluene, xylene, mineral spirits, naphtha, gasoline, acetone, methyl ethyl ketone, hexane, carbon disulfide, and others. 

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