基团贡献法估算烃的辛烷值

提出了两种用基团贡献法估算烃的辛烷值的方法 ,第一水平基团法和第二水平基团法。按在不同分子中相同原子带电量不变的原则划分出 2 4个第一水平基团和 31个第二水平基团 ,并用试验数据回归得到第一水平基团和第二水平基团对MON和RON的贡献值。用新方法对未参加回归的五种物质的辛烷值进行了预测 ,结果表明对于含有支链和环的烃应采用第二水平基团法估算其辛烷值 ,对简单的直链烃采用第一水平基团法估算其辛烷值

Estimating the Octane Number of Hydrocarbons

Two methods for estimating the octane number of hydrocarbons namely,the first level group contribution method and second level group contribution method were presented and assessed.Twentyfour first level groups and 31 second level groups were divided according to the principle that the charge of the same atom remains unchanged in different molecules,and the contribution parameters of the groups to MON and RON were obtained by correla ting the 168 MON and 119 RON experimental data.The octane number of 5 substances were predicted using the new methods.The results show that the second level group contribution method exhibits significant improvements in accuracy and should be used for estimating the octane number of branched and ring hydrocarbons.In cases of simple straight chain bydrocarbons,however,the first level group contribution method should be used.