In petroleums

Asphaltenes have high concentrations of heteroelements sulfur, nitrogen, nickel and vanadium. Their content varies widely in petroleum oils (Table 1.5). They cause a number of problems throughout the petroleum industry. 

Oxygen is present only in small quantities in petroleum as illustrated in Table 1.5, and its concentration is usually determined by subtracting the combined carbon, hydrogen, and nitrogen total from 100. 

Knowledge of sulfur content in petroleum products is imperative the analytical methods are numerous and depend on both the concentration being measured and the material being analyzed. 

The choice between X-ray fluorescence and the two other methods will be guided by the concentration levels and by the duration of the analytical procedure X-ray fluorescence is usually less sensitive than atomic absorption, but, at least for petroleum products, it requires less preparation after obtaining the calibration curve. Table 2.4 shows the detectable limits and accuracies of the three methods given above for the most commonly analyzed metals in petroleum products. For atomic absorption and plasma, the figures are given for analysis in an organic medium without mineralization. 

To extend the applicability of the characterization factor to the complex mixtures of hydrocarbons found in petroleum fractions, it was necessary to introduce the concept of a mean average boiling point temperature to a petroleum cut. This is calculated from the distillation curves, either ASTM or TBP. The volume average boiling point (VABP) is derived from the cut point temperatures for 10, 20, 50, 80 or 90% for the sample in question. In the above formula, VABP replaces the boiling point for the pure component. 

Molecular weight for a mixture of components such as one would encounter in petroleum cuts, the molecular weight is ... 

Nevertheless, we are witnessing most recently an important development in petroleum product specifications regarding two main factors ... 

Lowell, James D.(1985) Structural Styles in Petroleum Exploration, 460p, OGGI Publications... 

The hydrochloride of the amine may be prepared precisely as that of the primary amine. For recrystallisation, boil a suspension of the powdered salt in petroleum (b.p. 60-80°), and then add acetone slowly in small drops until the boiling suspension just becomes clear allow the stirred solution to cool until crystallisation starts, and then chill in ice-water before collecting the colourless plates of the hydrochloride, which after drying in a vacuum desiccator have m.p. 132-134°. 

Some alcohols react readily with phenylisocyanate at room temperature, and others require heating, preferably in petroleum. Phenylisocyanate is poisonous and should not be heated outside a fume-cupboard except under a condenser. 

D) Phenylurea Derivatives. This reaction usually proceeds readily when cold solutions of the dried amine and of phenyl isocyanate, each in petroleum (b.p. 100-120 ), are mixed if no reaction is obvious, heat under reflux for 30 minutes. Care in using the isocyanate, p. 336.)... 

Another procedure, which is sometimes adopted, consists in adding a susi)eiisioii of the adsorbent in petroleum ether (b.p. ca. 60-80°) in small... 

In the summer of 1963, I learned that I had won the American Chemical Society Award in Petroleum Chemistry for my work on Friedel-Crafts chemistry. It was a most welcome recognition for someone who only a few years earlier had fled his native country and started all over on a far-away continent. Although I have received numerous other awards and recognitions over the years, with the exception of the Nobel Prize, no other award touched me as much. 1 remember that my first ACS award carried with it a check for 5,000. My research director for some reason believed that a company employee was not... 

Alkvl Azides from Alkyl Bromides and Sodium Azide General procedure for the synthesis of alkyl azides. In a typical experiment, benzyl bromide (360 mg, 2.1 mmol) in petroleum ether (3 mL) and sodium azide (180 mg, 2.76 mmol) in water (3 mL) are admixed in a round-bottomed flask. To this stirred solution, pillared clay (100 mg) is added and the reaction mixture is refluxed with constant stirring at 90-100 C until all the starting material is consumed, as obsen/ed by thin layer chromatographv using pure hexane as solvent. The reaction is quenched with water and the product extracted into ether. The ether extracts are washed with water and the organic layer dried over sodium sulfate. The removal of solvent under reduced pressure affords the pure alkyl azides as confirmed by the spectral analysis. ... 

Cracking (Section 2 16) A key step in petroleum refining in which high molecular weight hydrocarbons are converted to lower molecular weight ones by thermal or catalytic carbon-carbon bond cleavage... 

Reforming (Section 2 16) Step in oil refining in which the pro portion of aromatic and branched chain hydrocarbons in petroleum is increased so as to improve the octane rating of gasoline... 

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