In this work, we present a model, based on rough hard-sphere theory, for the tracer diffusion coefficients of gaseous solutes in non-polar liquids. This work extends an earlier model developed specifically for carbon dioxide in hydrocarbon liquids and establishes a general correlation for gaseous solutes in non-polar liquids. The solutes considered were light hydrocarbons, carbon dioxide, nitrogen and argon, while the solvents were all hydrocarbon liquids. Application of the model requires knowledge of the temperature-dependent molar core volumes of the solute and solvent, which can be determined from pure-component viscosity data, and a temperature-independent roughness factor which can be determined from a single diffusion coefficient measurement in the system of interest. The new model was found to correlate the experimental data with an average absolute relative deviation of 2.7 %. The model also successfully represents computer-simulation data for tracer diffusion coefficients of hard-sphere mixtures and reduces to the expected form for self-diffusion when the solute and solvent become identical.

在这项工作中，我们提出了一个基于粗糙硬球理论的模型，用于非极性液体中气态溶质的示踪扩散系数。这项工作扩展了专门为碳氢化合物液体中的二氧化碳开发的早期模型，并建立了非极性液体中气态溶质的一般关联。考虑的溶质是轻烃、二氧化碳、氮气和氩气，而溶剂都是烃类液体。该模型的应用需要了解溶质和溶剂的温度相关摩尔核心体积，这可以从纯组分粘度数据中确定，以及与温度无关的粗糙度因子，可以从单个扩散系数测量中确定。兴趣系统。发现新模型将实验数据与 2.7% 的平均绝对相对偏差相关联。该模型还成功地表示了硬球混合物示踪剂扩散系数的计算机模拟数据，并在溶质和溶剂变得相同时简化为自扩散的预期形式。