Liquid Density and Critical Properties of Hydrocarbons Estimated from Molecular Structure

Abstract

The paper provides new correlations for the estimation of the relative liquid density and critical parameters of hydrocarbons. The correlations employ molecular descriptors from computer simulation of molecular mechanics, which proved valuable in our previous work. High precision is achieved, without the use of unduly complex descriptors and rules, as a result of improved methodology. The new methodology includes a limit upon the functionality of the property database and its predesign by expanding the range and improving the distribution of the repeating structural features in the selected compounds.A compilation of estimated data for the liquid density and critical properties of some hydrocarbons of industrial importance for which no values have been available before is provided.

Simulation of 1-alkene and n-alkane binary vapour–liquid equilibrium using different united-atom transferable force fields

“…The critical temperature for 1-octadecene from the simulations was estimated using a density scaling law [60] while the critical density was estimated using the law of rectilinear diameters [61]. The estimated critical density for 1-octadecene of 0.227, 0.221 and 0.224 g/cm 3 for the NERD, TraPPE and SA1 force fields, respectively, all compare favourably with the extrapolated critical density of 0.227 g/cm 3 of Wakeham et al [62]. However, while the estimated critical temperatures of 744 and 742 K for the NERD and TraPPE force fields, respectively, are in reasonable agreement with the experimental value of 748 K determined by Nitikin and Popov using a pulse-heating technique [63], the estimated critical temperature for 1-octadecene from the SA1 force field off 777 K is in substantial disagreement with the experimental value.…”

Semi-Empirical Models and Cubic Equations of State for Correlation of Solids Solubility in scCO2: From Simple to Complex Substances

“…The critical parameters were estimated applying the methods suggested in ref. [31,32]. With regard to calix [4]resorcinarene it should be noted that as this compound is an oligomer it can be treated as a conventional component and hence the above methods are applicable to estimate its critical properties.…”

Property prediction by similarity of molecular structures—practical application and consistency analysis

“…Structure-property relationships can also be derived by finding a set of most significant common features (SCF) of molecular structure relevant to a given property, out of a database containing a large number of molecular descriptors (Wakeham et al, 2002). The different molecular descriptors in the database may be computed by simulated molecular mechanics, quantum chemical methods, the topology of the molecules, etc.…”

“…The structure-structure correlations between molecular descriptors are derived from the database of Wakeham et al (2002) and Cholakov et al (1999), using the SROV program of Shacham and Brauner (2003). This database includes 99 molecular descriptors for 260 hydrocarbons.…”