共沸精馏脱高温费托合成C8馏分中的含氧化合物

摘要

After the components of high-temperature Fisher-Tropsch C8-cut was determined by chromatography-mass spectrum,the azeotropic distillation was carried out to remove the oxygenates from high-temperature Fisher-Tropsch C8-cut. PRO-Ⅱ was applied to simulate the distillation process by NRTL thermodynamic method. The separation process of the azeotropic distillation with ethanol/water solution as solvent was established. The effect of water content, theoretical stage number and feed stage number on the separation effect was investigated so as to get the best operational parameter for azeotropic distillation tower. Then,a bench-scale distillation column was used to verify the simulation for value by high-temperature Fisher-Tropsch C8-cut. The result showed that the oxygenates at the top was not detected and the mass fraction of the 1-octene at the bottom is less than 0.1%.The best operational parameters were as follows: water content in solvent was about 14% with the theoretical stage number of 30,the feed stage number of 17 and the solvent ratio of 1.2∶1.The experimental data matched well with those of the simulation.%在气相色谱-质谱联用（GC-MS）分析出高温费托合成C8馏分所有组分的基础上，以乙醇水溶液为溶剂，采用共沸精馏法对高温费托合成C8馏分脱含氧化合物。采用PRO-Ⅱ选择NRTL热力学方法对分离过程进行模拟，建立了共沸精馏分离工艺流程，并考察了共沸剂水含量、理论塔板数、进料位置等工艺条件对共沸精馏塔分离结果的影响，得到了最优操作条件，然后采用实验室小型精馏塔对高温费托合成 C8馏分进行实验验证。结果表明，塔顶采出液中未检测出含氧化合物，塔釜采出液中1-辛烯含量小于0.1%（质量分数），模拟最优条件为：共沸剂水含量为14%（质量分数），溶剂比为1.2∶1，理论塔板数30块、进料位置为第17块。实验与模拟值吻合良好。