Wide boiling range

Naphthenic acids occur ia a wide boiling range of cmde oil fractions, with acid content increa sing with boiling point to a maximum ia the gas oil fraction (ca 325°C). Jet fuel, kerosene, and diesel fractions are the source of most commercial naphthenic acid. The acid number of the naphthenic acids decreases as heavier petroleum fractions are isolated, ranging from 255 mg KOH/g for acids recovered from kerosene and 170 from diesel, to 108 from heavy fuel oil (19). The amount of unsaturation as indicated by iodine number also increases in the high molecular weight acids recovered from heavier distillation cuts. 

The ideal concept is usually a good approximation for close boiling components of a system, wherein the components are all of the same family of hydrocarbons or chemicals for example paraffin hydrocarbons. When odd or non-family components are present, the possibility of deviations from non-ideality becomes greater, or if the system is a wide boiling range of components. 

The equations for estimating nucleate boiling coefficients given in Section 12.11.1 can be used for close boiling mixtures, say less than 5°C, but will overestimate the coefficient if used for mixtures with a wide boiling range. Palen and Small (1964) give an empirical correction factor for mixtures which can be used to estimate the heat-transfer coefficient in the absence of experimental data ... 

Fifty milliliters of a liquid boils at 74.8° C from the beginning of the distillation to the end. Since there is no wide boiling range, can we assume that the liquid is pure ... 

This will not be true for mixtures with a wide boiling range). 

Note that, if the reacting system has a wide boiling range, the measured vapour pressure data will be different to that for the relieving reactor. The composition for the relieving reactor will change due to the preferential vaporisation of the most volatile component(s), but this will not be the case for the closed calorimetric test. 

Nickel and vanadium in petroleum exist as soluble organometallic complexes that fall into two categories metal porphyrins and nonporphyrin metal complexes. Both the porphyrins and the nonporphyrins may be distributed over a wide boiling range (350-650°C+), reflecting significant variations in molecular weight, structure, and polarity. Metal porphyrins and nonporphyrin metal complexes also tend to precipitate as part of the asphaltene materia] to an extent that varies with the source of the crude oil. 

The various methods for the experimental determination of boiling point of a liquid by distillation are discussed in Section 2.24 for sample sizes ranging down to about 0.5 ml. If the liquid is shown by distillation to have a wide boiling range (10-30 °C), it will be necessary to subject it to fractional distillation, or to one of... 

Because a refinery stream spans a wide boiling range, the crude oil analysis data would be accumulated throughout that range to provide fraction properties. The intent here is to demonstrate the relationship among volume distilled, boiling point, liquid density, and sulfur content. 

However, the reactivity and the wide boiling range of these compounds have caused considerable problems in analytical workup of the reaction mixtures, so that frequently only qualitative and semiquantitative results are recorded in the literature [2, 4],... 

JFor boiling of mixtures, the saturation temperature (bubble point) of the final liquid phase (after the desired vaporization has taken place) is to be used to calculate the mean temperature difference. A narrow-boiling-range mixture is defined as one for which the difference between the bubble point of the incoming liquid and the bubble point of the exit liquid is less than the temperature difference between the exit hot stream and the bubble point of the exit boiling liquid. Wide-boiling-range mixtures require a case-by-case analysis and cannot be reliably estimated by these simple procedures. 

Quin2,3 was the first to apply gas chromatography for the analysis of nicotine alkaloids in tobacco smoke. He used three sets of conditions to analyse the many alkaloids present in a wide boiling range. 

Today, normal refining processes for fuels and lubricants yield hundreds of different streams—fractions of narrow or wide boiling ranges and widely va rying chemical compositions. Even such impurities as hydrogen sulfide are available in quantity in a concentrated manner. When to these normal methods are added processes designed to produce or separate even more specific compounds or cuts for chemical use, it can be seen that the refiner of petroleum is in every sense the producer of a wide variety of chemical raw materials. In other words, the raw materials for chemicals from petroleum are, quite evidently, petroleum and the products that are produced in its refining to yield fuels and lubricants. 

A. E. Arbuzov and Razumov obtained diethyl 2-oxo-2-phenylethyIphosphonate in 1934 by the reaction of triethyl phosphite with 2-bromoacetophenone (Scheme 7.9). However, the authors found that the compound formed had an unusually wide boiling range ... 

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