Paraffin binaries

The densities of the naphthenic paraffins binary mixtures at all temperatures are in amazingly good agreement with the densities of the corresponding pure hydrocarbon. 

As expected, Equation 10 worked well for the 14 paraffin binaries the average deviation of the predicted from the optimum values was only 0.02. However, when all 26 hydrocarbon binaries were included, the average deviation increased to 0.05. 

Equation 11 was much less satisfactory, even when the coefficient was adjusted to minimize the deviation. The optimum value of the coefficient was 0.18, in agreement with Lin s conclusion for rare-gas mixtures, but the root-mean-square deviation of k j was 0.08. Any relationship involving I, the first ionization potential, is doomed to failure when applied to heavy hydrocarbon mixtures because I, for a given homologous series, is very weakly dependent on carbon number. For example, the I of n-decane is 10.19 eV, only 0.24 eV less than that of n-hexane, while that of n-eicosane should be about 10.04 eV. Thus, a correlation of kijs for methane-paraffin binaries based solely on ionization potentials would give the same result for all Ci0+ paraffins. 

Equation 12b works surprisingly well. Although it is inferior to Equation 11 when applied to the paraffin binaries (average deviation of 0.03 vs. 0.02), it comes out better when all hydrocarbon binaries are considered (average deviation of 0.04 vs. 0.05). Equation 12b is also satisfactory for the binaries of methane with Ar, Kr, N2, and H2S (average deviation of 0.01 vs. 0.03 with Equation 10), but is very poor for methane-H2. 

Teja (8) recommended Equation 15 (with 0.01 as the coefficient) for the paraffin binaries of ethane. 

Kato, K Nagahama, K Hirata, M. (1981). Generalized interaction parameters for the Peng-Robinson equation of state Carbon dioxide n-paraffin binary systems. Fluid Phase Equilib., Vol. 7, pp. 219-231... 

A significant advance in flame retardancy was the introduction of binary systems based on the use of halogenated organics and metal salts (6,7). In particular, a 1942 patent (7) described a finish for utilizing chlorinated paraffins and antimony(III) oxide [1309-64-4]. This type of finish was invaluable in World War II, and saw considerable use on outdoor cotton fabrics in both uniforms and tents. 

The exact formulations for inlay casting waxes are considered trade secrets, and Htfle has been pubUshed on the subject. A binary mixture of 65—75 wt % paraffin wax (60—63°C) and a microcrystalline wax having a melting point >60° C has been suggested (127). This produces a mixture having a sohd—sohd transition point at about 37°C with htfle plastic deformation (1—3%) at 37°C and a desirable plasticity at 45°C (73—77%) (128). 

Dilute Binary Hydrocarbon Mixtures Hayduk-Minhas presented an accurate correlation for normal paraffin mixtures that was developed from 58 data points consisting or solutes from C5 to C32 and solvents from C5 to Cig. The average error was 3.4 percent for the 58 mixtures. 

Matthews-Akgerman The free-volume approach of Hildebrand was shown to be valid for binary, dilute liquid paraffin mixtures (as well as self-diffusion), consisting of solutes from Cg to Cig and solvents of Cg and C o- The term they referred to as the diffusion volume was simply correlated with the critical volume, as = 0.308 V. We can infer from Table 5-15 that this is approximately related to the volume at the melting point as = 0.945 V, . Their correlation was vahd for diffusion of linear alkanes at temperatures up to 300°C and pressures up to 3.45 MPa. Matthews et al. and Erkey and Akger-man completea similar studies of diffusion of alkanes, restricted to /1-hexadecane and /i-octane, respectively, as the solvents. 

The interaction parameters for binary systems containing water with methane, ethane, propane, n-butane, n-pentane, n-hexane, n-octane, and benzene have been determined using data from the literature. The phase behavior of the paraffin - water systems can be represented very well using the modified procedure. However, the aromatic - water system can not be correlated satisfactorily. Possibly a differetn type of mixing rule will be required for the aromatic - water systems, although this has not as yet been explored. 

Temperature-dependent interaction parameters for selected paraffin-water binary systems... 

The agreement between the physical properties of the pure hydrocarbons and the binary physical mixture is much poorer for these hydrocarbons which contain the aromatic phenyl group than it is for the naphthenic-paraffinic mixtures. The derivatives for the aromatic mixtures are from four to nine times those of the physical mixtures of the pure hydrocarbons where no aromatic rings are present. 

Nitrogen dioxide was used in mixtures with such combustibles as paraffin (without aromatic compounds), carbon disulphide or nitrobenzene. These substances were used in the proportions necessary to give complete decomposition into C02, H20 and N2, thus permitting full utilization of the oxygen present in the nitrogen dioxide. To prevent the solidification of nitrobenzene at low temperatures a binary combustible constituent, e.g. a mixture of nitrobenzene with carbon disulphide, was used. 

The first PGSE investigation of a rubber-based ternary solution was described by Ferguson and von Meerwall31), who measured diffusion of C6F6(19F NMR) and n-paraffin (n-dodecane or n-hexatriacontane 1H NMR) in a commercial polybutadiene as function of both concentrations. They showed that both concentration dependences in the ternary region can be derived from the measured diffusivity of each diluent i = 1, 2 in binary solution in the rubber. To do this it was necessary to extend the Fujita-Doolittle expression, as follows ... 

The critical loci of binary systems composed of normal paraffin hydrocarbons are shown in Figure 2-16.2 Obviously, the critical pressures of mixtures are considerably higher than the critical pressures of the components of the mixtures. In fact, a larger difference in molecular size of the components causes the mixtures to have very large critical pressures. 

Fig, 2-16. Critical loci of binary n-paraffin mixtures. (Brown et al., Natural Gas and the Volatile Hydrocarbons, NGAA, 1947, 4, with permission.)... 

Although a typical natural gas is mainly comprised of the first three normal paraffins, the phase equilibria of each component with water will differ from that of a natural gas with water. However, a comparison of predictions with data for methane, ethane, and propane simple gas hydrates is given as a basis for understanding the phase equilibria of water with binary and ternary mixtures of those gases. 

Relative Adsorptivities for Binary n-Paraffin Systems over Various Zeolites... 

The viscosities of many binary liquid systems display minima as functions of composition at constant temperature, so that negative values of D are also possible. Yajnik and his coworkers (265 ) long ago observed that very frequently an extremum in the isothermal vapor pressure-composition curve is accompanied by an extremum of the opposite sense in the viscosity-concentration curve. Data are apparently not available for solutions of very low-molecular-weight paraffins in carbon tetrachloride, but minima are found for the viscosities of solutions of CC14 with ethyl iodide, ethyl acetate and acetone, so that a minimum appears quite probable for mixtures of small aliphatic hydrocarbons with carbon tetrachloride. If this were true, the downward trend of the Meyer-Van der Wyk data on C17—C31 paraffins, earlier discussed in connection with the polyethylene plots of Fig. 14, would be understood. It will be recognized that such a trend is also precisely what is to be expected from the draining effect of the hydrodynamic theories of Debye and Bueche (79), Brinkman (45 ) and Kirkwood and Riseman (139). However, the absence of such a trend in the case of polyethylene... 

Hydrocarbon. A binary compound of carbon and hydrogen a general term which includes the paraffin, olefin, aromatic, and all other series of hydrides of carbon. 

Poettmann, F.H. and Katz, D.L. 1945. "Phase Behavior of Binary Carbon Dioxide-Paraffin Systems", Ind. Eng. Chem., 37 847-853. 

Fig. 29. Critical loci of binary n-paraffin systema. (Brown, Katz, Oberfell, and Alden, Natural Oas and Volatile SydrocaTbons, 1948, p. 4.)...

Under more severe conditions, Pd or Pt-H-mordenite hydrocracks both paraffins and cycloparaffins, again being more active than the corresponding Y-type zeolite catalyst. We have found that n-Cc and n-Cj are converted essentially to C3 and i-C, whereas n-Cio gives i-C and i-Cs primarily. Although n-Ce and n-Cio paraflBns are hydrocracked more rapidly than the corresponding cycloparafiins (cyclohexane and decalin), with binary mixtures of paraffin and the corresponding cycloparaffin, the latter are removed preferentially (4, 24, 25). 

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