烷烃混合物二元相互作用参数的新型关联式

针对偏离二参数对应状态原理的复杂流体，以Mie势能函数和London色散力理论为基础，引入基于Joffee和Stewart虚拟临界规则的Leland分子形状系数，推导得到状态方程中二元相互作用参数k_ij的新型关联式.取Mie势能函数的参数n为3时，无需经过实验数据返算，关联式可直接计算和预测烷烃混合物k_ij;除了物质的临界性质外，k_ij还是温度、组成、摩尔体积、偏心因子和离子化势能的函数.将关联式初步应用于Peng-Robinson状态方程计算烷烃类混合物的临界压力，计算值与实验值平均偏差小于2.40％，取得满意的结果.

New correlation for binary interaction parameters of paraffins mixtures

Based on the Mie potential function theory and London dispersion forces theory, and with the introduction of Leland’s molecular shape factors to modify the inadequacy of the two parameters corresponding states principle for complex fluids, a new correlation for binary interaction parameters of the equation of state was proposed.The pseudocritical rules of Joffee and Stewart were introduced to evaluate the molecular shape factors of mixtures in the deduction process.When Mie potential constant was set to be 3, the new correlation obtained could be used to evaluate the binary interaction parameters of paraffins mixture without back-calculation.The new correlation showed that besides the critical properties of components in paraffins mixture,the binary interaction parameters were the function of composition, temperature, molar volume, acentric factor and component’s ionization potential.Satisfying results with the maximum average absolute error of 2.40%, were achieved when the correlation was used in the Peng-Robinson equation of state to calculate the critical pressure of paraffins mixture.