Asphalt elemental analysis

Although distillation and elemental analysis of the fractions provide a good evaluation of the qualities of a crude oil, they are nevertheless insufficient. Indeed, the numerous uses of petroleum demand a detailed molecular analysis. This is true for all distillation fractions, certain crude oils being valued essentially for their light fractions used in motor fuels, others because they make quality lubricating oils and still others because they make excellent base stocks for paving asphalt. 

Asphaltenes seem to be relatively constant in composition in residual asphalts, despite the source, as deterrnined by elemental analysis (6). Deterrnination of asphaltenes is relatively standard, and the fractions are termed / -pentane, / -hexane, / -heptane, or naphtha-insoluble, depending upon the precipitant used (5,6,49). After the asphaltenes are removed, resinous fractions are removed from the maltenes-petrolenes usually by adsorption on activated gels or clays. Recovery of the resin fraction by desorbtion is usually nearly quantitative. 

Table I. Elemental Analysis and Properties of Catalytic Cracking Feedstocks (Asphalt Ridge Bitumen)...

Thus elemental analysis is still of considerable value to determine the amounts of elements in asphalt, and the method chosen for the analysis may be subject to the peculiarities or character of the feedstock under investigation and should be assessed in terms of accuracy and reproducibility. The methods that are designated for elemental analysis are ... 

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