In petroleum products

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. 

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

Petroleum Products. Condensation products of sahcylaldehyde and amines ate used in various forms for the removal or neutralization of the metallic ions that cause oxidative degradation in petroleum products. The product formed from propylenediamine and sahcylaldehyde, ie,... 

Perhaps the biggest contribution that technological advancement in petroleum production will make is bringing large volumes of unconventional petroleum resources, eg, heavy oil and tar sands, into a viable economic realm by lowering the unit cost of production. Compared to the inventory of conventional petroleum reserves and undiscovered resources, the physical inventories of such unconventional petroleum resources are extremely large for example, the Athabasca tar sands in Alberta, Canada, are estimated to contain 360 x 10 m (2250 x 10 bbl) of in-place petroleum (19). This volume is equivalent to the total inventory, ie, the combined cumulative production, reserves, and undiscovered resources, of world conventional cmde petroleum. In... 

Another consideration of petroleum assessment analysts is whether, and to what degree, the vast resources of unconventional petroleum in the world can be captured by advances in petroleum production technologies, thereby converting them into conventional sources of petroleum. It is a simple fact that the ia-place resources of petroleum in tar sands, heavy oils, and oil shale can guarantee the future supply of petroleum for hundreds of years at the current rate of consumption, provided they can be produced at competitive costs. 

Corrosion Control in Petroleum Production, TPC5, National Association of Corrosion Engineers, Houston, Texas, 1984. 

Antirust properties of cargoes in petroleum product pipelines... 

Table 5-3. Comparison of Speed, Accuracy, and Cost for Determination of Sulfur in Petroleum Products...

B. M. Hegarty and R. Levy. Procedure for combatting biological contamination in petroleum production (procede pour combattre I encrassement biologique dans la production de petrole). Patent FR 2725754, 1996. 

Electrodes of the first kind have only limited application to titration in non-aqueous media a well-known example is the use of a silver electrode in the determination of sulphides and/or mercaptans in petroleum products by titration in methanol-benzene (1 1) with methanolic silver nitrate as titrant. As an indicator electrode of the second kind the antimony pH electrode (or antimony/antimony trioxide electrode) may be mentioned its standard potential value depends on proton solvation in the titration medium chosen cf., the equilibrium reaction on p. 46). 

The research was oriented towards the development of biocatalysts for removal of recalcitrant sulfur heterocyclic compounds including benzothiophenes, naphthothio-phenes, and alkylbenzothiophenes. To begin with, they focused on asymmetric sulfur compounds in this class and developed a method for desulfurization of these compounds present in petroleum products [108], The identity of the microorganisms was not disclosed in the abstract but they do claim use of the enzymes as well in the application. 

In contrast to infrared spectrometry there is no decrease in relative sensitivity in the lower energy region of the spectrum, and since no solvent is required, no part of the spectrum contains solvent absorptions. Oil samples contaminated with sand, sediment, and other solid substances have been analysed directly, after being placed between 0.5 mm 23-reflection crystals. Crude oils, which were relatively uncontaminated and needed less sensitivity, were smeared on a 2 mm 5-reflection crystal. The technique has been used to differentiate between crude oils from natural marine seepage, and accidental leaks from a drilling platform. The technique overcomes some of the faults of infrared spectroscopy, but is still affected by weathering and contamination of samples by other organic matter. The absorption bands shown in Table 9.1 are important in petroleum product identification. 

Table 9.1. Absorption bands important in petroleum products identification...

The sulfur compounds that are present in minor quantities in petroleum products also exhibit a typical gas chromatographic fingerprint easily obtained by flame photometric detection. This fingerprint has been introduced to complement the flame ionisation detection chromatogram with the aim of resolving the ambiguities or increasing the reliability in the identification of the pollutants [74]. 

It is generally agreed that worldwide petroleum supply will eventually reach its productive limit, peak, and begin a long term decline. One of the alternatives is the Nation s untapped oil shale as a strategically located, long-term source of reliable, affordable, and secure oil. The extent of U.S. oil shale resources, which amounts to more than 2 trillion barrels, has been known for a century. In 1912, the President established the Naval Petroleum and Oil Shale Reserves. There have been several commercial attempts to produce oil from oil shale, but these have failed because of the lower cost of petroleum at the time. With future declines in petroleum production, market forces are expected to improve the economic viability of oil shale. 

Despite the large number of hydrocarbons found in petroleum products aud the widespread nature of petroleum use and contamination, many of the lower-boiUng constituents are well characterized in terms of physical properties, but only a relatively small number of the compounds are well characterized for toxicity. The health... 

Many of the gaseous and liquid constituents of the lower-boiling fractions of petroleum and also those in petroleum products fall into the class of chemicals that have one or more of the following characteristics, considered to be hazardous by the EPA. 

As a resnlt of the wide variety of chemicals in petroleum and in petroleum products, it is not practical to measure each one separately. After an incident, it is more usual to measure the amount of total petroleum hydrocarbons at the site. The term total petroleum hydrocarbons (TPHs) is used environmentally to describe the family of several hundred chemical compounds that originally come from petroleum (Weisman, 1998). 

The most common method for GC/MS analysis of semivolatile compounds (EPA SW-846 8270) includes 16 polycyclic aromatic compounds, some of which commonly occur in middle distillate to heavy petroleum products. The method also quantifies phenols and cresols, compounds that are not hydrocarbons but may occur in petroleum products. Phenols and cresols are more likely found in crude oils and weathered petroleum products. 

The determination of nitrogen in petroleum products is performed regularly by the Kjeldahl method (ASTM D3228), the Dumas method, and the microcoulomet-ric (ASTM D3431) method. The chemiluminescence method is the most recent technique applied to nibogen analysis for petroleum and is used to determine the amount of chemically bound nitrogen in liquid samples. 

Being the third most common element (after carbon and hydrogen) in petroleum product, sulfur has been analyzed extensively. Analytical methods range from elemental analyses to functional group (sulfur-type) analyses to structural characterization to molecular speciation (Speight, 2001). Of the methods specified for the... 

A test method (ASTM D5291) is available for simultaneous determination of carbon, hydrogen, and nitrogen in petroleum products and lubricants. There are at least three instrumental techniques available for this analysis, each based on different chemical principles. However, all involve sample combustion, components separation, and final detection. 

Sieck, L.W. Determination of Molecular Weight Distribution of Aromatic Components in Petroleum Products by Cl-MS with Chlorobenzene As Reagent Gas. Anal. Chem. 1983,55,38-41. 

An example of beneficial metabolism is illustrated by the conversion of toluene, a volatile chemical present in petroleum products and readily absorbed through the lungs, to benzoic acid, as shown ... 

Cyclopentane and cyclohexane are commonly found in petroleum products like gasoline and are generically called yet another name, naphthenes in the refining business. 

Specialized properties that are not covered in these standard databases can be found in specialized books. The properties of food can be found in Physical Properties of Foods (Peleg and Bagley 1983). The properties of many petroleum products can be found in Petroleum Products Handbook (Guthrie 1960). The Merck Index (1996) lists chemicals, drugs, and biologicals. 

NACE International. 1993. Standard test method Determining the corrosive properties of cargoes in petroleum product pipelines. In Book of Standards.NACE Standard TM0172-93. Houston. 

Antifoam Agent An additive, usually silicone- or polyglycol-based, used to reduce foaming in petroleum products. 

Definite progress is being made in this direction despite the complexity of the problem. It appears that the major accomplishments of the future will be. based on the current research aimed at segregating and identifying the individual sulfur compounds in crude petroleum and in petroleum products. 

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