Aniline INDEX

Some empirical formulas have been devised to link the cetane index to the Diesel Index (D.l.) or even directly to the aniline point. We will cite two such formulas here in order to illustrate their comparative values C ... 

Other terms relating to physical properties include viscosity refractive index pour point, ie, the lowest temperature at which the oil flows flash point, ie, the temperature at which the oil ignites and aniline point, ie, the minimum temperature at which equal volumes of oil and aniline are completely miscible. These are determined under defined conditions estabHshed by ASTM. 

Other methods are also available for the estimation of diesel fuel quaUty. For example, the diesel index (DI) is defined by the relation DI = (A° F X ° API)/100, where A °F is the aniline point in degrees Fahrenheit and °API is the American Petroleum Institute gravity. A high aniline point corresponds to a high proportion of paraffins in the diesel fuel such a fuel has a high diesel index and, therefore, a high cetane number. 

Solubility of resins can be predicted in a similar way as for the solubility of polychloroprene rubbers in a solvent mixture (see Section 5.5) by means of solubility diagrams (plots of the hydrogen bonding index (y) against the solubility parameter (5). Another more simple way to determine the solubility of resins is the determination of the cloud point, the aniline and the mixed aniline points. 

Aniline point is used in some correlations to estimate the aromaticity of gas oil and light stocks. TOTAL S [1] correlation uses aniline point and refractive index. Others, such as n-d-M [2], employ refractive index to characterize FCC feed. 

Similar to aniline point, refractive index (RI) shows how refractive or aromatic a sample is. The higher the RI, the more the aromatics and the less crackable the sample. A feed having an RI of 1.5105 is more difficult to crack than a feed with an RI of 1.4990. The RI can be measured in a lab (ASTM D-1218) or predicted using correlations such as the one published by TOTAL. 

Trend the feedstock properties look for changes in the K factor, 1,050°F+ (565°C+), aniline point, refractive index, and °API gravity. The feed endpoint may have been increased to fill the unit. The conversion penalty may be a small price to pay for the increased capacity, but the penalty can be minimized. Verify that the refinery LP reflects current data on yields and product quality. 

Increase in naphthene, olefin, and aromatic concentration, which is indicated by an increase in the refractive index and decreases in aniline point and K factor... 

Track changes in feed metals content, trend the aniline point, and refractive index. 

Plot the feed refractive index, API gravity, and aniline point. Determine any shift in the amount of cracked gas oil in the feed. 

Refractive Index, similar to aniline point, is a quantitative indication of a sample s aromaticity. 

Evaluation of the only appropriate Fukui function is required for investigating an intramolecular reaction, as local softness is merely scaling of Fukui function (as shown in Equation 12.7), and does not alter the intramolecular reactivity trend. For this type, one needs to evaluate the proper Fukui functions (/+ or / ) for the different potential sites of the substrate. For example, the Fukui function values for the C and O atoms of H2CO, shown above, predicts that O atom should be the preferred site for an electrophilic attack, whereas C atom will be open to a nucleophilic attack. Atomic Fukui function for electrophilic attack (fc ) for the ring carbon atoms has been used to study the directing ability of substituents in electrophilic substitution reaction of monosubstituted benzene [23]. In some cases, it was shown that relative electrophilicity (f+/f ) or nucleophilicity (/ /f+) indices provide better intramolecular reactivity trend [23]. For example, basicity of substituted anilines could be explained successfully using relative nucleophilicity index ( / /f 1) [23]. Note however that these parameters are not able to differentiate the preferred site of protonation in benzene derivatives, determined from the absolute proton affinities [24],... 

Some halo-substituted anilines are of limited thermal stability, tending to eliminate hydrogen halide which may catalyse further decomposition. To avoid decomposition during distillation, this should be conducted in the presence of solid alkali or magnesium oxide at minimum temperature (under relatively high vacuum) and/or with exclusion of air by inert gas. Individually indexed compounds are 4-Bromoaniline, 2296... 

Many of the reactions of A-chloro- and A-bromo-imides are extremely violent or explosive. Those observed include A-chlorosuccinimide with aliphatic alcohols or benzylamine or hydrazine hydrate A-bromosuccimmidc with aniline, diallyl sulfide, or hydrazine hydrate or 3-nitro-A-bromophthalimide with tetrahydrofur-furyl alcohol l,3-dichloro-5,5-dimethyl-2,4-imidazolidindione with xylene (violent explosion). Individually indexed compounds are ... 

Kirk Othmer II (1966), 864 l-Azido-2-iodobenzene, C6H4N3I mw 245.03, N 17.15% strong smelling oil, bp 90-91° at 0.9 mm Hg, d 1.8893 at 25°, refractive index 1.6631 at 25° prepd by diazotizing aniline with NaN3. No expl props are reported. The l-Azido-3-iodo- and 1-Azido-4-iodo-derivs are also known (Ref 2)... 

Pearce et al, (21) pointed out that changes in boiling point, number of carbon atoms, aniline point, refractive index, density, and gravity within a series of fractions of an oil are proportional to the change in molecular weight. The relationships observed in plotting correlations of efficiency to these factors would be similar to those illustrated by correlar tion with molecular weight. 

Excellent agreement was also found for viscosity index, refractive index, and aniline point. 

Multiple Melting Points A compound may have different crystal structures (i.e., solid phases). For example, carbon tetrachloride has three known solid phases at atmospheric pressure la (face-centered cubic), lb (rhombohedral), and II (monoclinic). Ia and lb melt at temperatures some 5K apart [3]. Multiple melting points have been reported for a large set of compounds, such as many of those listed in the Merck Index [4], Dearden and Rahman improved a structure-melting point correlation for substituted anilines by excluding two outliers on the ground that their Tm values were inadequate, due to different crystalline forms [5]. 

With other solvents, e.g., oil of turpentine, pinewood oil, light mineral oils, resin, tar, shale or camphor oil, the density and boiling point may be determined and various other determinations made, such as the rotation, refractive index, solubility in aniline, behaviour towards fuming nitric acid. The special reactions of resin oil, pinewood oil, shale oil and camphor oil may also be applied. 

Diesel index an approximation of the cetane number (q.v.) of diesel fuel (q.v.) calculated from the density. v.) and aniline point (< .v.). 

Where Tb is the molal average boiling point of the fraction in degrees Rankin and s is the specific gravity of the Iraction. The K-factor can be correlated with other physical parameters of the fraction API gravity and viscosity API gravity and flash point API gravity and aniline point flash point and refractive index. 

The work of Migal and Belotskii (1402) furnishes a good example of the difficulties that can arise. Their extensive and careful work shows only slight indications of interactions detected by density or surface tension measurements of ethanol-aniline, whereas their viscosity and refractive index data do not show complex formation at all. In the ethanol-CHCU system none of their tests shows interaction. 

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