Determination of the octane number of a fuel by the IR spectroscopy method

The near-IR spectroscopy method of control of the octane number (o.n.) of a fuel is studied. An analysis is made of a device developed as an alternative of a measuring system based on a nonselective IR radiation source and of an analyzer based on a laser semiconductor diode. It is shown that the use of the methods of multicomponent regression analysis of spectral data allows measurement of the octane number with an accuracy of S ∼ 0.17 octane number units. The characteristics of the semiconductor laser-based analyzer are investigated and the parameters of radiators are discussed that provide the required sensitivity of the measuring system (up to 10−4 with respect to optical absorption) in controlling the octane number of a fucl.