Diesel fuels methanol blends

Methanol is more soluble in aromatic than paraffinic hydrocarbons. Thus varying gasoline compositions can affect fuel blends. At room temperature, the solubiUty of methanol in gasoline is very limited in the presence of water. Generally, cosolvents are added to methanol—gasoline blends to enhance water tolerance. Methanol is practically insoluble in diesel fuel. 

Biofuels. Biofuels are Hquid fuels, primarily used ia transportation (qv), produced from biomass feedstocks. Identified Hquid fuels and blending components iaclude ethanol (qv), methanol (qv), and the ethers ethyl /-butyl ether (ETBE) and methyl /-butyl ether (MTBE), as well as synthetic gasoline, diesel, and jet fuels. 

Soybean oil is converted into soy FAME through transesterification with methanol. This product is an excellent substitute for diesel fuel with no engine adjustment required and no loss in efficiency (Knothe Dunn, 2005). Besides transesterification to methyl esters, other approaches also were explored for utilizing soybean oil as fuel. These are diluted with conventional petroleum diesel fuel, microemulsions (co-sol-vent blending), and pyrolysis (Schwab et al., 1987). A detailed discussion on biodiesel is provided in the Chapter Bioenergy and Biofuels from Soybeans, and also elsewhere (Knothe Dunn, 2005 Reaney et al., 2004). 

Besides producing mixed-hydrocarbons (ultra-clean diesel), F-T process can also selectively produce mixed-alcohols (oxygenated fuel). The addition of mixed-alcohols into gasoline can effectively reduce HC and CO emissions. However, before directly used as fuels or blended with conventional fuels, the water content in the as-produced F-T mixed-alcohols must be reduced below 0.5wt.%. This dehydration step is essential but difficult since most of the contained alcohols form azeotropies with water. In our group, we studied the dehydration performance of microwave synthesized NaA zeolite membrane toward F-T produced mixed-alcohols [24, 25]. The membrane also showed excellent pervaporation performance toward dehydration of simulated F-T produced mixed-alcohols. The permeate consisted of only water and little methanol (< 10%) in aU the range of feed composition. This result confirmed that NaA zeolite membrane based pervaporation (or vapor permeation) process could be an effective technology for dehydration of F-T produced mixed-alcohols. 

Nitroparaffins are used in diesel fuel to increase power output of engines. Nitropropane is completely miscible in diesel fuel, nitroethane solubility is 18 wt%, and nitromethane is only a 2 wt%. Nitromethane is used as a fuel in racing cars and in model engines. A blend of nitromethane and methanol is said to produce increased power output over regular hydrocarbon fuels. 

Ethanol and methanol have cetane values from 0 to 5 making them poor compression ignition fuels for a diesel engine. However, alcohol-diesel fuel blends have been used successfully, and emulsifiers have been added to help blend the two components which have limited miscibility. 

Nitroparaffins are not explosives as determined by tests approved by the U.S. Department of Transportation (DOT) for shipping classifications. However, nitromethane when sensitized by small amounts of amines can be detonated by a Number 8 blasting cap. Nitromethane is used as a fuel component in ammonium nitrate explosives. Nitroparaffins are used in diesel fuel to increase power output of engines. Nitropropane is completely miscible in diesel fuel, nitroethane solubility is 18 wt%, and nitromethane is only a 2 wt%. Nitromethane is used as a fuel in racing cars and in model engines. A blend of nitromethane and methanol is said to produce increased power output over regular hydrocarbon fuels. 1-Nitropropane is used as a grinding solvent for the production of aluminum powder because of its ability to displace surface moisture on the aluminum and the solvent aids in the dispersion of the aluminum powder. Nitromethane is used as a metal stabilizer for... 

Biodiesel is a renewable nonpetroleum-based diesel fuel, which consists of monoalkyl (mainly methyl, ethyl, or propyl) esters of long chain fatty acids produced from vegetable oils or animal fats by transesterification with methanol or ethanol. Certain fuel characteristics have made biodiesels an attractive alternative liquid fuel to be used as such or as a constituent of a blend with petro diesel (Delfort et al., 2008). It is known to enhance engine performance through its better lubricity and more complete burning (Pramanik and Tripathi, 2005 Boumay et al., 2005 Knothe et al., 2005). It has a high flash point, better viscosity, and a caloric... 

Owing to its properties, methanol is not recommended for aircraft or marine fuel uses. Methanol caimot be used in conventional diesel-powered vehicles without modifications to the fuel system and engine. Simple methanol—diesel blends are not possible because of insolubiUty. Heavy-duty diesel engines have been adapted to use neat methanol by many U.S. manufacturers, and several are being used in field demonstrations (82) (see Alcohol fuels). 

Many GTL-derived fuels are being considered for blending with gasoline and diesel to achieve emission reductions of particulate matter (PM), carbon monoxide (CO), nitrogen compounds (NOx) and nonmethane hydrocarbons (NMHC). The most promising fuels converted from natural gas are methanol and ethers such as dimethyl ether (DME) and mcthyl-t-bntyl ether (MTBE). 

Methanol, which is also known as wood alcohol, is a colorless and odorless liquid alcohol fuel that can be made from biomass, natural gas, or coal. It is the simplest alcohol chemically and it may be used as an automobile fuel in its pure form (Ml 00), as a gasoline blend of typically 85% methane to 15% unleaded gasoline (M85). It is also used as a feedstock for reformulated gasoline. M100 or pure methanol may be used as a substitute for diesel. In M85, the gasoline is added to color the flame of burning fuel for safety reasons and to improve starting in cold weather. 

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