Abstract: The simulation study of separating 1,2,4-trimethylbenzene from C9 aromatics was carried out using chemical flowsheet simulation software Aspen Plus and selecting PR-BM equation as thermodynamic model. Through comparing and analyzing the simulation results of various separation processes, it can be seen that using double-effect heat integration distillation technology can significantly reduce the energy consumption of distillation process. The energy saving rate can reach 64.79 %，the product purity and yield are 98.51 % and 90.54 %, respectively.

Key words: 1,2,4-trimethylbenzene, separation process, heat integration, energy saving, multi-effect distillation