Automatic Determination of Aniline Point of Petroleum Products

Abstract

An apparatus is described for the automatic determination of aniline point of petroleum products. The basic principle involved comprises the use of the electric eye as a substitute for visual observation. The test sample is internally heated or cooled, the temperature is maintained uniform by stirring, and temperature equilibrium is automatically accomplished by a relay system. The relay system which controls the heating or cooling is activated by directing a light beam through the sample on a photocell, the light beam being interrupted periodically as the sample clears or clouds with slight temperature change. The Flashing of a lamp bulb indicates when equilibrium temperature is reached. THE A.S.T.M. defines aniline point (1) as "the minimum equilibrium solution temperature for equal volumes of aniline and petroleum product".

Automatic Operations in Analytical Chemistry

“…Presumably the temperature at this point could be automatically recorded. A fundamentally similar device for automatic determination of the aniline points (48) of petroleum products involves photoelectric detection of the clearing of the clouded solution which occurs at the aniline point temperature.…”

Characterization and identification of lipids by their critical solution temperatures

“…The temp readings can be rendered difficult due to color, the formation of precipitations or the occurrence of isooptieai mixtures (the refractive indices of both liquids become identical) (22). Refinements in observation of CSTvalues or methods of expediting the procedure have been described by m~merous authors (3,7,21). In contrast to melting point determinations, super cooling does not occur.…”