中文摘要：

为 CH4， C2H4 和 iso-C4H10 的二进制、第三的混合物的蒸汽液体平衡(VLE ) 性质在从作为溶剂与 iso-C4H10 包含 CH4 和 C2H4 的混合的乙烯的恢复是很重要的。因此，吉布斯整体蒙特卡罗(GEMC ) 模拟被用来与统一原子潜力书呆子模型一起为 CH4， C2H4 和 iso-C4H10 的二进制、第三的混合物估计蒸汽液体平衡。选择模拟条件在文学基于实验。这个工作的结果被显示在对状态的 Peng-Robinson 方程的可得到的试验性的数据和预言的令人满意的同意。模仿的液体阶段的结构被光线的分发功能(RDF ) 也描绘，它贡献这些系统的 VLE 曲线的进一步的理解。RDF 不对压力和温度范围敏感。随压力的增加或温度的减少，分子趋于一起聚在一起。

英文摘要：

The vapor-liquid equilibrium（VLE） properties for the binary and ternary mixtures of CH4,C2H4 and isoC4H10 are of great importance in the recovery of ethylene from mixture containing CH4 and C2H4 with iso-C4H10 as solvent.Hence,Gibbs ensemble Monte Carlo（GEMC） simulations were used to estimate vapor-liquid equilibrium for the binary and ternary mixtures of CH4,C2H4 and iso-C4H10 with the united atom potential NERD model.The selected simulation conditions are based on the experiment in the literature.The results of this work were shown to be in satisfactory agreement with available experimental data and predictions of Peng-Robinson equation of state.The structure of simulated liquid phase is also characterized by radial distribution function（RDF）,which contributes to further understanding of the VLE curve of these systems.RDF is not sensitive to the pressure and temperature range.With the increase of pressure or the decrease of temperature,the molecules tend to gather together.