Petroleum distillation products, major

Crude oil is the source for over. 1,(1(1() petroleum-based products for both industrial and consumer applications. The technique of distillation, the first stage processing of petroleum, exploits the different boiling points of the various petroleum fractions to separate out and isolate for use the different portions of the crude. The type and proportions of hydrocarbons present in each fraction depends upon the type of crude oil used and the range of temperatures employed. The major products produced directly... 

This section describes the major industrial processes within the petroleum refining industry, ineluding the materials and equipment used, and the processes employed. The section is necessary for an understanding of the interrelationships between the industrial processes, the types of air emissions, and control and pollution prevention approaehes. Deseriptions of eommonly used production processes, assoeiated raw materials, by-produets produeed are first deseribed. Petroleum refining is the physieal, thermal, and chemical separation of erude oil into its major distillation fraetions, which are then further proeessed through a series of separation and eonversion steps into finished petroleum produets. The primary products of the industry fall into three major categories ... 

Since the majority of middle distillates are used as a fuel, combustion of these products will contribute to SO2/SO3 air pollution and acid rain. However, in catalytic processes of petroleum fractions Sulfur levels are also important. Lor instance, quantities... 

Naphtha a generic term applied to refined, partly refined, or unrefined petroleum products and liquid products of natural gas, the majority of which distills below 240° C (464°F) the volatile fraction of petroleum which is used as a solvent or as a precursor to gasoline. 

Petroleum crude and its refinery products have two major component based on distillation. The portion that can be distilled under refinery conditions can be called volatiles and the nondistillables are the nonvolatiles. The volatiles can be analyzed by GC or GC-MS. The crude has both components. The distillate as the names applied, such as naphtha and kerosene contain only volatiles. When GPC is used for analyzing various distillates, the fractions separated by GPC can be characterized by GC or GC-MS. These data can be used to verify the nature of components present in various distillation cuts as a function of GPC elution volume. If the samples such as crude contains both volatiles as well as nonvolatiles, the samples should be separated into volatiles and nonvolatiles. The GPC of both components should be used to calibrate the GPC of the total crude. The parameter that can be obtained from GPC is effective molecular length. It can be used to relate other molecular parameters of interest after calibration. 

Furfural is obtained commercially by mealing pentosan-rich ugricullural residues (corncobs, oat hulls, cottonseed hulls, hagasse. rice hulls) with a dilute acid and removing the furfural by steam distillation. Major industrial uses of furfuraldehyde include (1) the production of t urnns and tetrahydrofurans where the compound is an intermediate (2) Ihc solvent refining of petroleum and rosin products (3) the solvent binding of bonded phenolic products and (4) the extractive distillation of butadiene from other C4 hydrocarbons. 

It is important to use rather pure acid esters for the resolution step. The hydrogen phthalates are usually solids that may be crystallized from petroleum ether, benzene, or acetic acid. Phthalic acid is the usual major impurity and may interfere with the crystallization of the ester. If it does, or if the ester is liquid, it is convenient to extract the crude product with chloroform or benzene, in which phthalic acid is nearly insoluble. Distillation of the solvent from the dried extract usually leaves the ester pure enough to crystallize or to use directly. 

A polar liquid phase was found more suitable for studying the major components of petrol, gas oil and diesel oil [3], forming true solutions in water. With such a phase, saturated hydrocarbons tended to elute before aromatic hydrocarbons, which were found to be the principal components in true solution, and therefore their investigation was facilitated, in the case of gas oil and diesel oil, forming true solutions in water. In the case of gas oil and diesel oil, no saturated hydrocarbons could be detected in solution. These authors reached the important conclusion that the determination of the origin of oil components in true aqueous solution could be more difficult because of selective solution of certain components. This effect was more likely to apply to the lower distillates, which tended to be relatively more water soluble, rather than the non volatile petroleum products. Distinction between petrol and gas oil or diesel oil seemed possible, but appeared difficult between similar products such as gas oil and diesel oil. 

The first step in refining petroleum is a careful fractional distillation. The products of that distillation are not pure alkanes but mixtures of alkanes with useful ranges of boiling points. Table 3-3 shows the major fractions obtained from the distillation of crude petroleum. 

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