دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a substance, such as tetraethyl lead or other compounds, added to the fuel of an internal-combustion engine to prevent detonation of the fuel. Antiknock compounds effectively raise the octane rating of a fuel so that it burns properly in the combustion chamber of an engine. See octane rating, tetraethyl lead.

n: 1. the breaking down of low temperatures and pressures.2. a motor gasoline refining process in which heavy hydrocarbon components are broken down into light hydrocarbon components using catalysts and relatively low temperatures and pressures. It produces a gasoline that has a higher octane rating and a lower sulphur content than that produced by thermal cracking.

n: 1. an explosion. 2. the knock or ping produced when fuel of too-low octane rating is used in the engine. Compare preignition.

n: in petroleum refining, the process of altering the arrangement of the atoms in the molecule without adding or removing anything from the original material. Straight-chain hydrocarbons are converted to branched-chain hydrocarbons with a substantially higher octane rating in the presence of a catalyst at moderate temperatures and pressures. The process is basic to the conversion of normal butene into isobutane.

n: see octane rating.

n: a classification of gasoline according to its antiknock qualities. The higher the octane number, or rating, the greater the antiknock qualities of the gasoline.