改进对应态基团贡献法用于纯物质偏心因子估算

Estimation of eccentric factor for pure substances by improved Corresponding State Group Contribution method

将对应态基团贡献法(CSGC)提出的拟临界性质应用于Lee-Kesler方程,提出新的纯物质偏心因子ω估算方程(CSGC-LK方程),对包括烷烃、烯烃、炔烃、卤代烷烃、环烷烃、环烯烃、二烯烃、醇、醚、酮、酸与酸酐、醛、酯、含硫化合物、含氮化合物、含氧多基化合物、芳烃、卤代苯和酚等20类376种物质偏心因子数据采用非线性最小二乘法进行关联,得到CSGC-LK方程的8个常数值和69种基团贡献参数值,ω总平均相对误差为5.47%。为进一步考察CSGC-LK方程的预测精度和适用范围,对7种未参加回归物质的偏心因子进行了预测,ω总平均误差为3.46%,预测精度良好。

Through introducing the assumed-critical properties given by Corresponding State Group Contribution （CSGC） into the Lee-Kesler equation,a new method （CSGC-LK） for estimating the eccentric factors ω of pure substances was proposed. 8 parameters and the contributions values of 69 groups in CSGC-LK equation were obtained with nonlinear least square method by correlating the properties of 376 organic materials in 20 classes,including alkanes,alkene,alkynes,haloalkanes,cyclohydrocarbons,cycloalkene,allenes,alcohol,ether,ketone,acid and acid anhydride,aldehyde,ester,and compounds containing oxygen,sulfur and nitrogen etc. The total regression average relative deviation of ω is 5.47%. In order to further investigate the predicted accuracy and application scope of CSGC-LK equation,the eccentric factors of 7 kinds of compounds which were not involved in the reunification were forecasted. The total average relative deviation of ω is 3.46%. The results obtained are satisfactory.