Boiling range for

Table V shows that in the Platformate a fairly uniform octane number is attained over the entire boiling range as compared to a decreasing octane number over the boiling range for the thermal reformate. This characteristic of the Platformate is particularly desirable because the octane number of the fuel to the various engine cylinders is relatively uniform regardless of intake manifold distribution effects.

Fractionation of petroleum in the refinery, to obtain streams with specific boiling ranges for various downstream processes, is performed by distillation in a crude unit. To determine how Ni and V compounds are distributed as a function of boiling point is, therefore, useful for evaluating their impact in the refinery. Petroleum may also be fractionated by solvent separation and chromatography to obtain more detailed information on the distribution of Ni and V compounds. This section will review the available literature on how metals are distributed in petroleum by boiling point and solubility class. It will also include some discussion of the structure of heavy oil in general and asphaltenes in particular. Vercier etal. (1981) have provided an excellent review of methods and procedures involved in petroleum fractionations. 

Because of the high molecular weight materials at the upper end of the boiling range for medium lube oil stocks, the desorption technique of choice should probably employ a displacement chemical with a high heat of adsorption, in order to overcome the high heat of adsorption of the in-paraffins. Ammonia at temperatures near 660 K and near atmospheric pressure appears to have good potential. 

Taking this into consideration, specifications (as in the U.S.S.R.) require a fairly narrow boiling range for xylene, for example, 95% of the product should distil between 136.5-140°C or 136.5-141.5°C. 

Crude oil fuels such as gasoline, kerosene and diesel and most intermediate streams in oil refinery consist of many different hydrocarbon compounds. The number of possible hydrocarbon isomers present depends on the carbon number, and both increase with boiling range. For diesel, crude oil, and heavy fuel oils, the... 

Figure 1. Boiling point versus carbon number for the constituents of petroleum. The constituents of petroleum fall into molecular weight and boiling ranges for which the knowledge of model compounds is limited.

It is a solvent for many resins. Hydrocarbon solvent with a boiling range for the commercial product (175-205°C), slightly higher than that for mineral spirit. Sp gr, 0.894/20°C flp, 60°C (140°F) refractive index, 1.467 and vp, 2mmHg/30°C. In Europe, Decaline. 

Aliphatic hydrocarbons are usually supplied as mixtures, because of the difficulty of separating the individual compounds. These are all distillates from petroleum refining (Chapter 3). A boiling range for the mixture is usually quoted, e.g. SBP (special blend of petroleum) spirit No. 3, 98-122 °C. Many mixtures also contain a percentage of aromatic hydrocarbons, e.g. white spirit, 155-195 °C, contains about 15% aromatic, though this may be absent in so-called low odour grades. 

Additional fractionation is required to separate the cracking byproducts into their appropriate boiling ranges for product blending. All the C4 and lighter hydrocarbons are compressed and sent to absorbers. The butanes are removed by absorption into gasoline blend cuts. The lighter components are then fractionated. 

Methyl Cyclohexyl Stearate n CH3(CH2)i6 COOC6H10CH3. Boiling range for the commercial product, 220-240°C/4 mmHg flp, 170°C (338°F). 

Recommended ASTM Boiling Ranges for Products Atmospheric Tower ... 

The importance of boiling range for petroleum products already has been discussed in connection with Table 15.5. The simplest form of refining would isolate crude oil into... 

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