Determination of Aromatics, Naphthenes, and Paraffins By Refractometric Methods

Abstract

Methods are described for determining aromatics, naphthenes, and paraffins in virgin naphthas and condensates boiling below 320°F. Most individual hydrocarbons can be estimated to 243°F. Efficient fractionation is used to produce narrow-boiling-range fractions containing relatively few individual hydrocarbons. Densities and refractive indices for the mercury g line and the sodium D line, deter-

Analysis of East Texas Virgin Naphtha Fractions Boiling up to 270� F

“…The Ce and Ce hydrocarbons can be determined by means of distillation and refractive index measurements (4, 8). In the C7 and higher boiling ranges, overlap between closely boiling isomers is encountered on distillation, and grouping of similar isomers in the analytical results is required, although some individual compounds boiling as high as 2430 F. have been identified (7). Mass spectrometry has also been applied through the C7 and higher fractions, although the grouping of various isomers having similar mass patterns is necessary {2).…”

Superfractionation studies - Composition and Octane Numbers of 0.5% Fractions of an Oklahoma City Naphtha

“…interval. These fractions were analyzed by specific dispersion (S) and refractivity intercept (2) methods to estimate the composition in terms of individual hydrocarbons. The data from these analyses and the best blending values available for the engine ratings of individual hydrocarbons were used to calculate the octane numbers of some of the cuts from the pilot plant stills.…”

Use of Physical Constants in Analysis Extension to Liquid Halogen and Oxygen Organic Compounds

“…Campbell and Thomas (S, 4), as well as Francis (6), used this principle to measure the thickness of metal films.…”