IFP Energies nouvelles, Rueil-Malmaison, France.
J Phys Chem B. 2012 Jan 12;116(1):367-77. doi: 10.1021/jp209313a. Epub 2011 Dec 12.
In this work, we propose a new methodology to determine association scheme and association parameters (energy and volume) of a SAFT-type EoS for hydrogen-bonding molecules. This paper focuses on 1-alkanol molecules, but the new methodology can also be applied for any other associating system. The idea is to use molecular simulation technique to determine independently monomer and free hydrogen fractions from which the association scheme can be deduced. The 3B scheme thus appeared to be the most appropriate for 1-alkanols. Once the association scheme is defined, the association strength can be back-calculated from molecular simulation results and used as an independent property for the equation of state parameters regression, in addition of the classical phase properties such as vapor pressure and liquid molar volume. A new set of parameters for 1-alkanol for the PPC-SAFT equation of state has been proposed following this methodology. Results are found in good agreement with experimental data for both phase properties and free hydrogen-bonding sites. Hence, this new methodology makes it possible to optimize parameters allowing an accurate reproduction of pure compounds data and yielding physically significant values for associating energy and associating volume.
在这项工作中，我们提出了一种新的方法来确定氢键分子的 SAFT 型状态方程的关联方案和关联参数（能量和体积）。本文的重点是 1-烷醇分子，但新方法也可应用于任何其他缔合体系。该方法的思路是使用分子模拟技术来独立确定单体和游离氢分数，从而可以推导出关联方案。因此，3B 方案似乎是 1-烷醇最合适的方案。一旦确定了关联方案，就可以从分子模拟结果中反推关联强度，并将其用作状态方程参数回归的独立性质，除了经典的相性质（如蒸气压和液体摩尔体积）之外。本文提出了一种新的适用于 PPC-SAFT 状态方程的 1-烷醇参数集。结果与相性质和游离氢键位置的实验数据吻合良好。因此，这种新方法使得可以优化参数，从而能够准确再现纯化合物数据，并为关联能量和关联体积提供具有物理意义的值。
