The. progress made in analytical mass spectrometry is reviewed from its start in 1942. Early work is mentioned only briefly but more recent work concerned with type analysis and particularly that utilizing elevated temperature is dwelt on at some length. A method for analyzing gasoline in terms of four compound types viz.
total paraffins,
total cycloparaf fins and monoolefins combined,
aromatics and
a group consisting of cyclomonoolefiris, diolefins and acetylenes is described.
By utilizing u heated sample introduction system certain compound types in gas oil and waxes may be determined.
L'exposé passe en revue les progrès réalisés en spectrométrie analytique de masse depuis ses débuts en 1942. Les premiers travaux ne sont que brièvement mentionnés mais il est insisté un peu plus sur les travaux plus récents relatifs à l'analyse des composants-types en particulier ceux utilisant des températures élevées. La communication décrit une méthode pour analyser l'essence en termes de quatre composants types, savoir I) paraffines totales, 2) cycloparaf f ines totales et mono-oléf ines combinées, 3) aromatiques et 4) un groupe formé des cyclomonooléfines, dioléfines et acétylènes. En se servant d'un dispositif pour l'introduction d'un échantillon chauf - fb, on peut déterminer certains types composés dans le gas oil et la paraffine.
Since the mass spectrometer was introduced as an analytical instrument to the petroleum industry in 1942, considerable progress has been made in applying it to a wide variety of analytical problems. At present, in the United States, there are approximately 100 of these general purpose analytical instruments in operation, most of which are in the petroleum industry, although, in recent years a number of chemical * The Atlantic Refining Company, Philadelphia, Penna, U%4. companies have become aware of the capabilities of the mass spvctrometer and have added it to their laboratories. The term general purpose has been applied here to differentiate the instrument used for broad analytical work from recently developed, limited purpose isotope ratio or leak detecting mass spectrometers, and from specialized specbometers operating on different principles such as the radio frequency (I) *, magnetic resonance (8), or time of flight instruments (9). Of the analytical instruments in operation, over 90% are manufactured by Consolidated Engineering Corporation; others were made by Westinghouse a number of years ago, but this company has since discontinued making them.
General Electric is now manufacturing a general purpose instrument and it is understood that Metropolitan Vickers in England is entering the field. Little is yet known, however, about the performance of these newer instruments.
Itiitially, the analytical mass spectrometer was designed for
