Acid
An acid results in a pH lower than 7 when dissolved in water.
Alkaline
A base results in a pH higher than 7 when dissolved in water.
Biodiesel
A diesel fuel substitute, additive or extender. Biodiesel is typically made from oils such as soyabeans, rapeseed, or sunflowers. There are three standard blends: Biodiesel B5, B20 and B100 where the number indicates the percentage of biodiesel in the finished fuel.
Bioethanol
Ethanol made from a variety of organic materials including biomass and the traditional feedstocks (starch and sugar crops). Ethanol is generally blended with gasoline at a ratio of 10% ethanol and 90% gasoline (E10). Ethanol can also be used in higher concentrations such as E85 or in its pure form.
Biofuel
A common term used for all liquid fuels for transportation, such as ethanol and biodiesel that are made from biomass such as E10 (the number after the letter represents the percentage of biodiesel or bio-ethanol in the fuel).
Biogas
A methane-rich gas, which is produced by the fermentation of animal dung, human sewage or crop residues. It is used as a fuel to heat stoves, lamps, run small machines and to generate electricity. Biogas fuels do not usually cause pollution, and because they come from renewable energy resources they have great potential for future use.
Biomass
Organic materials that can be used to produce energy or converted into a gas and used for fuel. Biomass sources include forest and mill residues, agricultural crops and wastes, wood and wood wastes, animal wastes, fast-growing trees and plants, and municipal and industrial wastes.
Learn more about converting biomass to fuel.
Black liquor
Mixture of spent cooking chemicals and dissolved wood material remaining after sulphate cooking.
C5 sugars
5 carbon sugars (pentoses) include e.g. ribose
C6 sugars
6 carbon sugars (hexoses) include e.g. glucose
Cellulase
A family of enzymes that break down cellulose into simple sugars.
Cellulose
A polysaccharide carbohydrate composed of beta-1,4 linked glucose units. Cellulose is the main consituent of plant cell walls and is the most common organic compound on earth.
CO2
Carbon dioxide. A greenhouse gas.
E-10
A mixture of 10% ethanol and 90% gasoline based on volume.
E-85
A mixture of 85% ethanol and 15% gasoline based on volume.
Energy crop
A crop grown specifically for its fuel value. These include food crops such as corn and sugarcane, and nonfood crops such as poplar trees and switchgrass. Energy crops are the raw materials used to produce bio-ethanol.
Enzyme
A protein or protein-based molecule that speeds up chemical reactions occurring in living things. Enzymes act as catalysts for a single reaction, converting a specific set of reactants into specific products. For more general information about enzymes and what they can do, visit the Novozymes website.
Ethanol
Ethyl alcohol produced by fermentation and distillation. An alcohol compound with the chemical formula CH3CH2OH formed during sugar fermentation.
Feedstock
A feedstock is a substance used as a raw material in an industrial process.
Fermentation
The biological conversion of biomass. Fermentation is one of many steps in the processing of biomass.
Fossil fuel
A carbon or hydrocarbon fuel formed in the ground from the remains of dead plants and animals. It takes millions of years to form fossil fuels. Oil, natural gas and coal are fossil fuels.
Glucose
A simple six-carbon sugar C6H12O6. A product of hydrolysis of glucans found in cellulose and starch.
Hemicellulose
This layer that surrounds the cellulose in plant fibres is a more complex structure of both C5 and C6 sugars.
Hydrolysis
A chemical reaction that in the ethanol production process breaks down starch or cellulose into simple sugars, which are normally linked together in complex chains. In ethanol production, hydrolysis reactions are used to break down starch into simple sugars. For biomass, enzymes break down the cellulose and hemicellulose into simple sugars. One of the steps in converting biomass to fuel.
Lignin
The major noncarbohydrate, polyphenolic structural constituent of wood and other native plant material that encrusts the cell walls and cements the cells together.
Lignocellulose
A combination of lignin and cellulose that strengthens woody plant cells.
Municipal solid waste (MSW)
Any organic matter, including sewage, industrial, and commercial wastes, from municipal waste collection systems. Municipal waste does not include agricultural and wood wastes or residues. MSW is one potential raw material that can be used to produce bio-ethanol.
MTBE
Methyl t-butyl ether - an oxygenate additive in gasoline. One of the main benefits of fuel ethanol is that it can replace the use of MTBE in gasoline.
Oxygenate
An oxygenate is a compound which contains oxygen in its molecular structure. Ethanol and biodiesel act as oxygenates when they are blended with conventional fuels. Oxygenated fuel improves combustion efficiency and reduces tailpipe emissions of CO.
Polysaccharide
A carbohydrate consisting of a large number of linked simple sugar, or monosaccharide, units. Examples of polysaccharides are cellulose and starch.
Residue
Unused solid or liquid by-products of a process.
Stover
The dried stalks and leaves of a crop remaining after the grain has been harvested. Stover is an agricultural waste, one type of raw material that can be used to produce bio-ethanol.
Substrate
A substance acted upon by an enzyme.
