Petroleum matrix

Poly(phenylene sulfide) (PPS) is another semicrystalline polymer used in the composites industry. PPS-based composites are generally processed at 330°C and subsequently cooled rapidly in order to avoid excessive crystallisation and reduced toughness. The superior fire-retardant characteristics of PPS-based composites result in appHcations where fire resistance is an important design consideration. Laminated composites based on this material have shown poor resistance to transverse impact as a result of the poor adhesion of the fibers to the semicrystalline matrix. A PPS material more recently developed by Phillips Petroleum, AVTEL, has improved fiber—matrix interfacial properties, and promises, therefore, an enhanced resistance to transverse impact (see PoLYAffiRS containing sulfur). 

Actual responses of tuo carbonate petroleum reservoirs to matrix injection of hydrochloric acid are compared with a recently proposed experimental model for wormholing. This model is shown to be applicable in undamaged primary porosity reservoirs, and should be useable in damaged double porosity ones. Formations of no primary porosity are shown to respond very differently. 

Petroleum petroleum pitch delayed coke, calcined coke needle coke, carbon fibers, binder and matrix carbon1... 

WOLF, B.P., SUMNER, L.W., SHIELDS, S.J., NIELSEN, K., GRAY, K.A., RUSSELL, D.H., Characterization of proteins utilized in the desulfurization of petroleum products by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, Anal. Biochem., 1998,260,117-127. 

Atomic absorption spectrometry is one of the most widely used techniques for the determination of metals at trace levels in solution. Its popularity as compared with that of flame emission is due to its relative freedom from interferences by inter-element effects and its relative insensitivity to variations in flame temperature. Only for the routine determination of alkali and alkaline earth metals, is flame photometry usually preferred. Over sixty elements can be determined in almost any matrix by atomic absorption. Examples include heavy metals in body fluids, polluted waters, foodstuffs, soft drinks and beer, the analysis of metallurgical and geochemical samples and the determination of many metals in soils, crude oils, petroleum products and plastics. Detection limits generally lie in the range 100-0.1 ppb (Table 8.4) but these can be improved by chemical pre-concentration procedures involving solvent extraction or ion exchange. 

Soxhlet, sonication, supercritical fluid, subcritical or accelerated solvent, and purge-and-trap extraction have been introduced into a variety of methods for the extraction of contaminated soil. Headspace is recommended as a screening method. Shaking/vortexing is adequate for the extraction of petroleum hydrocarbons in most environmental samples. For these extraction methods, the ability to extract petroleum hydrocarbons from soil and water samples depends on the solvent and the sample matrix. Surrogates (compounds of known identity and quantity) are frequently added to monitor extraction efficiency. Environmental laboratories also generally perform matrix spikes (addition of target analytes) to determine if the soil or water matrix retains analytes. 

Another method (EPA 3545, accelerated solvent extraction) has been validated using a variety of soil matrixes, ranging from sand to clay. In the method, conventional solvents such as methylene chloride (or a hexane-acetone mixture) are heated [100°C, (212°E)] and pressurized (2000 psi), then passed through the soil sample (this technique is also suitable for application to petroleum sludge and petroleum sediment). The method has the advantage of requiring smaller solvent volumes than is required by traditional solvent extraction techniques. 

Although these methods measure different petroleum hydrocarbon categories, there are several basic steps that are common to the analytical processes for all methods, no matter the method type or the environmental matrix. In general, these steps are (1) collection and preservation—requirements specific to environmental matrix and analytes of interest (2) extraction so that separations of the analytes... 

In general, it is not possible to differentiate among the thermal desorbers based on cost. The costs are scale dependent, ranging from 90 to 130 per ton ( 99 to 143 per metric ton) for a 1000-ton (907-metric ton) site to 40 to 70 ( 44 to 77 per metric ton) for a 10,000-ton (9070-metric ton) site for mobile systems treating petroleum-contaminated soils and from 300 to 600 per ton ( 331 to 661 per metric ton) for a 1000-ton (907-metric ton) site to 150 to 200 ( 165 to 220 per metric ton) for a 10,000-ton (9070-metric ton) site mobile system operating at a Superfund site. Matrix moisture and contaminant type are critical parameters in analyzing desorption costs (D12901B, p. 2.5). 

Some petroleum products, especially those containing higher-molecular-weight compounds such as waxes, do not crystallize rapidly when cooled. Instead, they form a gel-like network throughout the fuel matrix. This network can begin forming at temperatures well above the pour point of a fuel and may render the product unpumpable. 

A population-based case-control study on brain cancer was carried out in some areas in the United States with petroleum refining and chemical manufacturing industries (i.e., activities suspected of being associated with brain cancer) and is described in detail in the monograph on dichloromethane (see this volume). Probability, intensity, duration and calendar time of life-long individual exposures to each of six chlorinated aliphatic hydrocarbons, including 1,1,1-trichloroethane, were assessed through an ad-hoc job-exposure matrix. Whereas risk excesses of some consistency were associated with exposure to other chlorinated aliphatic hydrocarbons, exposure to 1,1,1-trichloroethane showed little indication of an association with brain cancer (Heineman et al., 1994). 

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