Hydrocarbon Types

The most important factor for maturation and hydrocarbon type is therefore heat. The increase of temperature with depth is dependent on the geothermal gradient which varies from basin to basin An average value is about 3°C per 100 meters of depth. 

Figure 5.21 Pressure temperature phase envelopes for main hydrocarbon types...

D. B. Broughton and L. C. Hardison, "Hydrocarbon-Type Separation by Unisorb," Paper presented at the 27th Midyear Meeting of the American Petroleum Institute, Division of Refining, San Erancisco, Calif., May 15, 1962. 

Absolute. This is concentrated extract obtained by treatment of a concrete or other hydrocarbon-type extract of a plant or plant part with ethanol. It is usually Hquid and should be totally soluble in alcohol. By this method, waxes, hydrocarbons (including terpenoid), as well as most of the odorless material of the concrete are removed from the extract. 

Petroleum, and the equivalent term cmde oil, cover a vast assortment of materials consisting of gaseous, Hquid, and soHd hydrocarbon-type chemical compounds that occur in sedimentary deposits throughout the world (3). When petroleum occurs in a reservoir that allows the cmde material to be recovered by pumping operations as a free-flowing dark- to light-colored Hquid, it is often referred to as conventional petroleum. 

Because of the unusual reactivity of the DCPD molecule, there are a number of wide and varying end use areas. The primary uses in the U.S. are DCPD-based unsaturated polyester resins (36%) hydrocarbon type resins, based on DCPD alone or with other reactive olefins (39%) EPDM elastomers via a third monomer ethylidenenorhornene or DCPD (16%) and miscellaneous uses (9%), including polychlorinated pesticides, polyhalogenated flame retardants, and polydicyclopentadiene for reaction injection mol ding (39). 

The polarity of the polyethers makes them incompatible with hydrocarbon-type plasticizers, which tend to bleed. Effective plasticizers are ethers such as di(butoxyethoxyethyl)formal [143-29-3] (Thiokors TP-90B), esters such as di(2-ethylhexyl) phthalate [117-81-7] dioctyl phthalate (DOP), polyesters such as Paraplex G50 (Rohm and Haas), and ether—esters such as di(butoxyethoxyethyl) adipate [114-17-3] (Thiokol s TP-95). The lower mol wt plasticizers, DOP, TP-90B, and TP-95 improve vulcanizate low temperature performance. The polymeric plasticizers maintain higher temperature and long-term aging properties. Epoxidized plasticizers should be avoided because they interfere with vulcanization. 

Fuel modification in terms of volatility, hydrocarbon types, or additive content. Some of the fuels currently being used are liquefied petroleum gas (LPG), liquefied natural gas (LNG), compressed natural gas (CNG), fuels with alcohol additives, and unleaded gasoline. The supply of some of these fuels is very limited. Other fuel problems involving storage, distribution, and power requirements have to be considered. 

J. J. Szakasits and R. E. Robinson, Hydrocarbon type determination of naphthas and catalytically reformed products hy automated multidimensional gas cliromatography . Anal. Chem. 63 114-120(1991). 

Refrigerant number of column one corresponds to the A.S.R.E. standard designation, which agrees with previous designations for the chloro-fluoro hydrocarbon type refrigerants. 

Paraffins are relatively inactive compared to olefins, diolefins, and aromatics. Few chemicals could be obtained from the direct reaction of paraffins with other reagents. However, these compounds are the precursors for olefins through cracking processes. The C -Cg paraffins and cycloparaffms are especially important for the production of aromatics through reforming. This section reviews some of the physical and chemical properties of C1-C4 paraffins. Long-chain paraffins normally present as mixtures with other hydrocarbon types in different petroleum fractions are discussed later in this chapter. 

The hydrocarbon types in the FCC feed are broadly classified as paraffins, olefins, naphthenes, and aromatics (PONA). 

It is important to characterize FCC feeds as to their molecular structure. Once the molecular configuration is known, kinetic models can be developed to predict product yields. The simplified correlations above do a reasonable job of defining hydrocarbon type and distribution in FCC feeds. Each correlation provides satisfactory results within the range for which it was developed. Whichever correlation is used, the results should be trended and compared with unit operation. 

The main mobile source of NO is the combustion of a fuel in an internal mbustion engine. Because aromatics have the highest combustion temperature among hydrocarbon types (see Figure 10-2), they... 

Non-polar hydrocarbon-type liquid phases, e.g. paraffin oil(Nujol), squalane, Apiezon L grease and silicone-gum rubber the latter is used for high-temperature work (upper limit 400°C). 

To retain solutes selectively by dispersive interactions, the stationary phase must contain no polar or ionic substances, but only hydrocarbon-type materials such as the reverse-bonded phases, now so popular in LC. Reiterating the previous argument, to ensure that dispersive selectivity dominates in the stationary phase, and dispersive interactions in the mobile phase are minimized, the mobile phase must now be strongly polar. Hence the use of methanol-water and acetonitrile-water mixtures as mobile phases in reverse-phase chromatography systems. An example of the separation of some antimicrobial agents on Partisil ODS 3, particle diameter 5p is shown in figure 5. 

IR and Raman spectroscopic studies on films and powders of PDHS indicate that the hexyl side chains are crystallizing into a hydrocarbon type matrix (40). This is indicated by the presence of a number of sharp characteristic alkane bands which become dramatically broadened above the transition temperature. Similar changes are observed for n-hexane below and above the melting point. CPMAS 29Si NMR studies on PDHS also show that the rotational freedom of the side chains increases markedly above the transition temperature (41,42). All of the spectral evidence... 

Blaylock JW, Bean RM, Wildung RE (1974) Determination of extractable organic material and analysis of hydrocarbon types in lake and coastal sediments. Special publication no. 409. National Bureau of Standards, Washington, DC, p 217... 

Tena et al. [52] carried out a screening of polyaromatic hydrocarbon types in soil by on-line fibre optic interfaced supercritical fluid extraction spectrofluorimetry. 

These values are then multiplied by a correction factor to account for hydrocarbon viscosity. Correction factors for different hydrocarbon types are... 

Extent of contamination/plume stability Hydrocarbon type Chromatographic evidence Hydrocarbon concentration Soil pH... 

Extractives of resinous materials by a hydrocarbon type solvent. The extractives are both volatile and non-volatile materials, and the resinous substance used is non-cellular in nature, e.g. Olibanum resinoid. 

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