Aromatic hydrocarbons parameters

As can be seen in Figure 8, different petroleum components measure processes across different source rock temperatrrre and maturity ranges with biomarkers being most active and abundant at low source maturity and light hydrocarbons and aromatic hydrocarbons being more dominant later in the oil window. However, even the more reliable light hydrocarbon and aromatic hydrocarbon parameters still represent the behaviour of mixtures. 

Wiliams D E 1965 Non-bonded potential parameters derived from crystalline aromatic hydrocarbons J. Chem. Phys. 45 3770... 

Random comparisons of predictions with 2.26 versus 2.6 show no consistent advantage for either value, however. It has been suggested to replace the exponent of 0.6 with 0.7 and to use an association factor of 0.7 for systems containing aromatic hydrocarbons. These modifications, however, are not recommended by Umesi and Danner. Lees and Sarram present a comparison of the association parameters. The average absolute error for 87 different solutes in water is 5.9 percent. 

The solubility parameter is in the range 18.4-19 MPa and the polymer is predictably dissolved by halogenated and aromatic hydrocarbons of similar solubility parameter. Stress cracking can occur with some liquids. 

Radical cations can be derived from aromatic hydrocarbons or alkenes by one-electron oxidation. Antimony trichloride and pentachloride are among the chemical oxidants that have been used. Photodissociation or y-radiation can generate radical cations from aromatic hydrocarbons. Most radical cations derived from hydrocarbons have limited stability, but EPR spectral parameters have permitted structural characterization. The radical cations can be generated electrochemically, and some oxidation potentials are included in Table 12.1. The potentials correlate with the HOMO levels of the hydrocarbons. The higher the HOMO, the more easily oxidized is the hydrocarbon. 

The above values are applicable only in the limiting case of infinite dilution. The interaction parameter varies with the volume fraction of polymer network as has been demonstrated for the PDMS-benzene system by Flory (47) and PDMS-methyl ethyl ketone, PDMS-methyl isobutyl ketone, PDMS-ethyl-n-butyl ketone, and PDMS-diisobutyl ketone by Shiomi et al. (48). Theoretically calculated and experimentally observed values of X as a function of volume fraction of polymer are given for PDMS in alkanes, aromatic hydrocarbons, and dimethyl siloxane oligomers by Gottlieb and Herskowitz (49). In the case of PDMS-alkanes, x was practically independent of the volume fraction of polymer. 

Kamlet, M. J., Doherty, R. M., Carr, P. W., Mackay, D., Abraham, M. H., Taft, R. W. (1988) Linear solvation energy relationships. 44. Parameter estimation rules that allow accurate prediction of octanol/water partition coefficients and other solubility and toxicity properties of polychlorinated biphenyls and polycyclic aromatic hydrocarbons. Environ. Sci. Technol. 22, 503-509. 

E. B. Ledesma, N. D. Marsh, A. K.Sandrowitz, and M. J. Womat, Global kinetic rate parameters for the formation of polycycUc aromatic hydrocarbons [PAH] from die pyrolysis of catechol A model compound representative of soUd fuel moieties. Energy Fuels 16(6), 1331—1336... 

Thus, electrochemical data involving both thermodynamic and kinetic parameters of hydrocarbons are available for only olefinic and aromatic jr-systems. The reduction of aromatics, in particular, had already attracted much interest in the late fifties and early sixties. The correlation between the reduction potentials and molecular-orbital (MO) energies of a series of aromatic hydrocarbons was one of the first successful applications of the Hiickel molecular orbital (HMO) theory, and allowed the development of a coherent picture of cathodic reduction [1], The early research on this subject has been reviewed several times [2-4],... 

Transferability of atomic densities was tested by Brock et al. (1991), who applied atomic charge density parameters from an accurate low-temperature study of perylene (I) to data collected at five and six different temperatures on naphthalene (II) and anthracene (III), respectively. The molecules are all aromatic hydrocarbons. To reduce the number of variables, all H atoms were assigned... 

Murk, A.J., Bosveld, A.T.C., Berg, M. van den and Brouwer, A. (1994a). Effects of polyhalogenated aromatic hydrocarbons (PHAHs) on biochemical parameters in chicks of the common tern (Sterna Hirundo). Aquat. Toxicol. 30(2), 91-115. 

Figure 8.2. Relation of solubility parameters (solpars or Hildebrand values) to boiling points and flash points, where A boiling points of aliphatic hydrocarbons B = flash points of aliphatic hydrocarbons C = boiling points of aromatic hydrocarbons D = flash points of aromatic hydrocarbons.

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