American Society for Testing and Materials or ASTM A non-profit technical organization that provides a management system to develop published technical information. Standards, test methods, specifications and procedures developed by this group are recognized as definitive guidelines for motor fuel quality as well as a broad range of other products and procedures.
Aromatics A group of hydrocarbon fractions that form the basis of most organic chemicals so far synthesized. Benzene, toluene and xylene are the principle aromatics commonly referred to as the BTX group. They are one of the heavier fractions in gasoline.
Biodiesel An oxygenated fuel, primarily alkyl (methyl or ethyl) esters, produced from a range of biomass-derived feedstocks including oilseeds, waste vegetable oils, cooking oil, animal fats and trap grease, which can be used in blends or in "neat" form in compression-ignition engines to reduce emissions and improve engine performance.
Biomass Any renewable organic matter such as agricultural crops, crop-waste residues, wood, animal and municipal wastes, aquatic plants and fungal growth used for the production of energy.
Bromine Number Bromine, a halogen element that is a dark-reddish, fuming, toxic liquid, used chiefly in the manufacture of anti-knock compounds, pharmaceuticals and dyes. Bromine number is the number of graphs of bromine which will react with 100 grams of the sample under the conditions of the test.
Carbon Monoxide A colorless, odorless gas. It is poisonous if inhaled because it combines with blood hemoglobin to prevent oxygen transfer. It is very slightly lighter than air. It is produced by the incomplete combustion of fuels with a limited oxygen supply, as in auto engines. It is a major component of urban air pollution, which can be reduced by the blending of an oxygen-bearing compound such as ethanol into hydrocarbon fuels.
Clean Air Act The first modern environmental law to be enacted by any nation, going into effect initially in 1963. Since then, a series of amendments to this original law has been enacted; in 1970 with the creation of the U.S. Environmental Protection Agency and again in 1977 and 1990. This law has established certain targets, standards and procedures for reducing human and environmental exposures to a range of pollutants generated by industry and transportation, including certain "criteria pollutants" such as lead, ozone, carbon monoxide, sulfur dioxide, oxides ofnitrogen and particulates, as well as air toxics. The law has set emissions standards for stationary sources such as factories and mobile sources such as automobiles and trucks.
Environmental Protection Agency or EPA A U.S. agency, established in 1970, responsible for the protection of the environment, air and water, regulation of radiation, toxics and solid wastes, including motor fuels and fuels additives such as ethanol-gasoline blends.
Ethanol Otherwise known as ethyl alcohol or "alcohol," or "grain-spirits." Ethanol can be produced chemically from ethylene or biologically from the fermentation of various sugars from carbohydrates found in agricultural crops and cellulosic residues from crops or wood. Used in the United States as a gasoline octane enhancer and oxygenate, it increases octane 2.5 to 3.0 numbers at ten percent concentration. Ethanol also can be used in higher concentration in vehicles optimized for its use.
Ethyl Tertiary Butyl Ether or ETBE A colorless, flammable, oxygenated hydrocarbon. The chemical formula is C2H5OC4H9. It may be produced from ethanol and tertiary butanol, or isobutylene. It is of similar structure to methyl tertiary butyl ether or MTBE and has similar octane-enhancing properties.
Fungible Literally means "interchangeable in trade." Commonly used to denote products which are suitable for transmission by pipeline. Ethanol is not considered fungible in this sense, in that it would absorb any water accumulating in pockets in a pipeline.
Lead, Tetraethyl Lead, Lead Alkyls A poisonous metallic anti-knock which is added to gasoline to increase the octane properties of the fuel. The chemical formula is Pb(C2H5)4.
Methanol or Methyl Alcohol A colorless poisonous liquid, with essentially no odor and very little taste. It is the simplest alcohol and has a formula CH3OH. It boils at 64.7ûC. It is miscible with water and most organic liquids, including gasoline. It is extremely flammable, burning with a nearly invisible blue flame. Methanol is produced commercially by the catalyzed reaction of hydrogen and carbon monoxide. It was formerly derived from the destructive distillation of wood, which caused it to be known as "wood alcohol."
Methyl Tertiary Butyl Ether or MTBE A colorless, flammable, liquid, oxygenated hydrocarbon. The chemical formula is (CH3)3COCH3. It contains 18.15 percent oxygen and has a boiling point of 55.2ûC. It is produced by reacting methanol with isobutylene. Its use as an octane enhancer in gasoline has been approved by the EPA, at levels of up to 15 percent.
Neat Alcohol Fuels This refers to the use of straight alcohol not blended with gasoline which may be either in the form of ethanol or methanol. In the case of ethanol as a neat alcohol fuel, there isn't a need for ethanol to be at 200 proof, so very often it is used at 180-190 proof or 90-95 percent. There is no advantage in making it anhydrous if it is not being mixed with gasoline. In Brazil, ethanol is sold at 180 proof for use as a neat alcohol fuel. In the case of methanol, most methanol fuels are not strictly "neat" as five-ten percent gasoline is usually blended in to improve its operational efficiency.
Nitrogen Oxides Air-polluting gases contained in automobile emissions, which are regulated by the EPA. They comprise colorless nitrous oxide otherwise know as di-nitrogen monoxide or as the anesthetic "laughing gas," a colorless nitric oxide and the reddish-brown-colored nitrogen dioxide. Nitric oxide is very unstable and on exposure to air it is readily converted to nitrogen dioxide, which has an irritating odor and is very poisonous. It contributes to the brownish layer in the atmospheric pollution over some metropolitan areas. Other nitrogen oxides of less significance are nitrogen tetroxide and nitrogen pentoxide. Nitrogen oxides are sometimes collectively referred to as "NOx" or "Nox" where 'x' represents any proportion of oxygen to nitrogen.
Nonattainment Area A region, determined by population density in accordance with the U.S. Census Bureau, which exceeds minimum acceptable National Ambient Air Quality Standards for one or more "criteria pollutants" as established in the Clean Air Act. Such areas are required to seek modifications to their state implementation plans, setting forth a reasonable timetable using EPA-approved means to achieve attainment of air quality standards for these criteria pollutants by a certain date. Under the Clean Air Act, if a nonattainment area fails to attain the standards, EPA may superimpose a federal implementation plan with stricter requirements or impose fines, construction bans, cutoffs in federal grant revenues, or other means, until the area achieves the applicable air quality standards.
Octane A flammable liquid hydrocarbon with a chemical formula of C8H18, which is found in petroleum. One of the eighteen isomers of octane, 2,2,4-trimethylpentane is used as a standard in assessing the octane rating of fuels.
Octane Rating The research octane number of a fuel plus the motor octane number of a vehicle divided by two equals the octane rating.
Octane Enhancer Any substance such as ethanol, methanol, MTBE, ETBE, benzene, toluene or xylene, which raises the octane rating when blended with gasoline.
Olefin Content A class of unsaturated hydrocarbons containing one or more double bonds and having the general chemical formula CnH2n.
Oxygenated Fuels Literally meaning any fuel substance containing oxygen, the term is commonly taken to cover fuels containing such oxygen-bearing compounds as ethanol, methanol, MTBE or other oxygenate. Oxygenated fuel tends to give a more complete combustion of its carbon into carbon dioxide rather than monoxide to reduce air pollution from exhaust emissions.
Ozone A form of oxygen molecule with three oxygen atoms with the chemical formula O3. Ozone occurs as a blue, toxic, pungent-smelling gas at room temperature. The ozone layer is a concentration of ozone molecules six-30 miles above sea level. The layer is in a state of dynamic equilibrium. Ultraviolet radiation forms the ozone from oxygen, but can also reduce the ozone back to oxygen. The process absorbs most of the ultraviolet radiation from the sun, shielding life from radiation's harmful effects. Certain air pollutants can drift up into the atmosphere and damage the balance between ozone production and destruction, resulting in a reduction of the concentration of ozone in the layer. Ozone is normally present at ground level in low concentrations. In cities where a high level of air pollutants are present, the action of the sun's ultraviolet light can, through a complex series of reactions, produce a harmful concentration of ozone in the air. The air pollution caused is called photo-chemical smog.
Reid vapor pressure A measure of the vapor pressure in pounds per square inch, of a sample of gasoline at 100ûF. It is an indication of the volatility of a gasoline. The blending of ethanol with gasoline tends to increase the Reid vapor pressure, while the blending of MTBE and more particularly, ETBE, tends to reduce the Reid vapor pressure.
Tax Incentives In general, a means of employing the tax code to stimulate investment in or development of a socially-desirable economic objective without the direct expenditure from the budget of a given unit of government. Such incentives can take the form of tax exemptions or credits.
United States Department of Agriculture or USDA A federal government department with the mission to improve and maintain farm income and to develop and expand markets for agricultural products. Through such agencies as the Farmers Home Administration and theCommodity Credit Corporation, the USDA has been involved in assisting the development of the ethanol industry.
United States Department of Energy or DOE A department of the federal government, established by the Carter Administration in 1977, to consolidate energy-orientated programs and agencies. The Department's mission includes the coordination and management of energy conservation, supply, information dissemination, regulation, research, development and demonstration. The Department includes an Office of Alcohol Fuels.
Volatility The tendency of a solid or liquid to pass into the vapor state at a given temperature. With automotive fuels, the volatility is determined by measuring the Reid vapor pressure.
Volatile Organic Compounds Air pollution gases contained in automobile emissions regulated by EPA. Volatile organic compounds are carbon-based emissions, released through evaporation and/or combustion, that combine with nitrogen oxide in the presence of sunlight to form ozone.