Petroleum production

Chapter 1. Composition of Crude Oils and Petroleum Products... 

Chapter r, COMPOSITION OF CRUDE OlLS AND PETROLEUM PRODUCTS... 

Chapter 1. COMPOSITION Of CRUDE OILS AND PETROLEUM PRODUCTS 7... 

Nitrogen is incorporated in a hexagonal ring having three double bonds. The compounds in this family are those which can give a basic character to petroleum products and are thus a poison to acid catalysts. 

Corresponding to ASTM D 86 (NF M 07-002), this method applies to gasolines, kerosenes, heating oils, and similar petroleum products. 

The complexity of petroleum products raises the question of sample validity is the sample representative of the total flow The problem becomes that much more difficult when dealing with samples of heavy materials or samples coming from separations. The diverse chemical families in a petroleum cut can have very different physical characteristics and the homogeneous nature of the cut is often due to the delicate equilibrium between its components. The equilibrium can be upset by extraction or by addition of certain materials as in the case of the precipitation of asphaltenes by light paraffins. 

Incidentally, numerous petroleum products, particularly those coming from conversion processes, are unstable with respect to oxidation and oxygen analysis is meaningful only if great precautions are taken during sample withdrawal and storage. 

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 petroleum industry faces the need to analyze numerous elements which are either naturally present in crude oil as is particularly the case for nickel and vanadium or those elements that are added to petroleum products during refining. 

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. 

As the boiling points increase, the cuts become more and more complex and the analytical means must be adapted to the degree of complexity. Tables 3.4 and 3.5 describe the most widely used petroleum product separation scheme and the analyses that are most generally applied. 

Aside from its obvious qualitative functions, infrared spectrometry is applied to several other kinds studies of petroleum products. 

In straight-run petroleum products which do not usually contain olefins, four types of hydrogen can be easily differentiated as seen in the spectrum in Figure 3.10 ... 

The Reid vapor pressure characterizes the light petroleum products it is measured by a standard test (refer to Chapter 7) which can be easily simulated. 

The Reid vapor pressure is generally barely different from the true vapor pressure at 37.8°C if the light gas content —methane, ethane, propane, and butane— of the sample is small, which is usually the case with petroleum products. The differences are greater for those products containing large quantities of dissolved gases such as the crude oils shown in Table 4.13. 

Characteristics of Petroleum Products for Energy Use (Motor ftiels - Heating fuels)... 

In this chapter, we will discuss petroleum products used for energy purposes, that is, motor fuels and heating fuels. Chapter 6 will be devoted to other products such as special gasolines, lubricants, petrochemical bases, and asphalts. 

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