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Dictionary

Organic Chemistry

Activated carbon is derived from charcoal, and is used as biochar. It is a form of carbon with a high degree of adsorption, due to small, low-volume pores (high microporosity) which increase the surface area.

Active Carbon

Activated carbon is derived from charcoal, and is used as biochar. It is a form of carbon with a high degree of adsorption, due to small, low-volume pores (high microporosity) which increase the surface area.

One gram of activated carbon has a surface area of approx. 1,300 m2. Activated carbon contains more than 90% carbon.

Activated carbon, coal and coke are derived from charcoal, coal, and coke respectively. Charcoal is produced by slow pyrolysis, in which wood or other organic material is heated in the absence of oxygen.

Pyrolysis

Pyrolysis involves high temperatures and an absence of halogens, such as oxygen, in which organic material will thermochemically decompose. Pyro is Greek for 'fire', and lysis is Greek for 'division of'.

The resulting chemical composition and physical phase changes are irreversible. An example is the production of char, a solid rich in carbon, from wood, or coke from coal. Products in industrial applications include activated carbon, methanol, charcoal, from wood, and pyrolysis is used in the production of PVC by the conversion of ethylene dichloride into vinyl chloride.

In plastics recycling, pyrolysis is used to turn waste plastics into usable oil, or inert substances for disposal. Pyrolysis is the process behind 'cracking' in which heavy hydrocarbons are converted into lighter fuels like petrol.

Ignition loss

Loss of ignition is an inorganic analytical chemistry test. A sample is heated till all volatile substances have escaped. The mass that remains (ashes in the case of organics) is the ignition loss, often expressed as a percentage of the original mass.

Hydrogenation

Hydrogenation is a chemical process through which hydrogen atoms are added to a molecule.

Hydrogenation is generally done via a catalyst, such as nickel or platinum, although high-temperature non-catalytic hydrogenation is also possible.

Applications include reduction or saturate organic compounds, such as an alkene, usually with hydrogen gas (H2).

Near-infrared spectroscopy NIRS

Near-infrared spectroscopy, NIRS, utilises the electromagnetic radiation range 700 - 2500 nm. It is used for deeper penetration of samples than is possible with other EMR spectra, such as mid-infrared radiation.

Near-infrared spectroscopy (NIRS) is a spectroscopic method used in pharmaceuticals, medical diagnostics (including blood sugar and pulse oximetry), food and agrochemical quality control. Its research applications include functional neuroimaging, sports medicine, ergonomics, brain computer interface, and neurology (neurovascular coupling).