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Excess molar volumes, (V E m ), have been derived from the literature viscosity data for the binary mixtures of benzene with n-hexane, n-octane, n-decane, n-dodecane, ntetradecane, and n-hexadecane as a function of composition at 298.15 K and atmospheric pressure conditions. The V E m values were found to be positive over the entire composition range for all mixtures. Concentration dependence of V E m were fitted with Redlich-Kister polynomial equation to estimate the binary coefficients and standard errors. From density data, the partial molar volumes (V m ), partial molar volumes at infinite dilution (V 0 m ), excess partial molar volumes at infinite dilution (V 0; E m ), and apparent molar volumes (V / ), were calculated over the whole composition range as were the limiting apparent molar volumes at infinite dilution (V 0 / ) and excess apparent molar volumes at infinite dilution (V 0; E / ). Viscosity of the binary mixtures of benzene with n-alkanes were estimated using Kendall-Monroe, Frenkel, Hind et al., Katti-Chaudhri, Grunberg-Nissan, Wilke and Herráez et al. equations. The agreement between experimental and predicted values for all systems was found to be quite reasonable as evidenced from computed standard deviation and average percentage deviation (APD). Wilke relation gives maximum deviations for all the systems in comparison to other methods employed. Other relations give comparatively good results.

Densities of aqueous solutions of Ethylene glycol (EG), diethylene glycol (DEG), and triethylene glycol (TEG) were measured at temperatures from 293.15 to 318.15 K and molalities ranging from 0.0488 to 0.5288 mol⋅kg −1 . Volumes of all investigated solutions at a definite temperature were linearly dependent on the solute molality; from this dependence the partial molar volumes at infinite dilution were determined for all solutes. It was found that the partial molar volumes at infinite dilution ( 2,0 ) were concentration independent and slightly increase with increasing temperature. The partial molar volumes at infinite dilution ( 2,0 ) or the limiting apparent molar volumes of ethylene glycols were fitted to a linear equation with the number of oxyethylene groups ( ) in the solute molecule. From this equation a constant contribution of the terminal (OH) and the (CH 2 CH 2 O) groups to the volumetric properties was obtained. The thermal expansion coefficient ( 1,2 ) for all investigated solutions was calculated at temperatures from 293.15 to 318.15 K. The thermal expansion coefficients for all solutes increase with increasing temperature and molality. Values of ( 1,2 ) were higher than the value of the thermal expansion coefficient of the pure water.

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This research describes the adsorption of phenol and o-substituted phenols and xylenol isomers on petroleum asphaltenes from aqueous solution. The results revealed that the adsorption equilibrium data were best fitted with the generalized and Freundlich isotherms. For o-substituted phenols, it was found that electron-withdrawing groups increase the adsorption capacity. The uptake of these phenols decreases in the order: o-nitrophenol > o-chlorophenol > o-aminophenol > o-cresol > phenol, while the adsorption of xylenol isomers decreases in the order: 2,6-xylenol > 2,5-xylenol > 3,5-xylenol > 3,4-xylenol. Batch equilibrium results at different temperatures suggest that the adsorption of 2,6-xylenol and 3,5-xylenol onto asphaltene is an endothermic process, Δ values obtained were positive indicating a nonspontaneous process with increasing randomness at the solid-solution interface. The influence of solution pH on the adsorption of 3,5-xylenol on asphaltenes was also investigated. The adsorption process was found to be independent on the solution pH. The adsorption capacity of 3,5-xylenol was found to increase with the decrease in particle size of the adsorbent.

The viscosities (η) and refractive indices (n D) were measured for the binary mixtures of o-cresol + PEG 200/PEG 300/PEG 400 over the whole composition range at five different temperatures (288.15, 293.15, 298.15, 303.15, and 308.15 K). From the experimental results, the viscosity deviation (Δη), the excess Gibbs free energy of activation of viscous flow (ΔG *E), the deviation in refractive index (Δϕ n D), and the molar refraction (R m) have been calculated. The excess or deviation properties were fitted with Redlich–Kister polynomial equation and their coefficients and standard deviations were calculated. The positive and negative excess or deviation properties were discussed in terms of specific molecular interactions between mixture components. The excess or deviation property values (Δη, ΔG *E, and Δϕ n D) follow the order PEG400 > PEG300 > PEG200. On the basis of the viscosity data, Gibbs energies of viscous flow (ΔG*), enthalpy of activation of viscous flow (ΔH*), and entropy of activation of viscous flow (ΔS*) were also calculated.