Simulation and Analysis of the Cascade Process for ¹³⁶Xe Isotope Separation Based on Microchannel Distillation Technology

Conventional distillation methods face significant challenges in xenon isotope separation. This paper proposes a cascaded distillation system based on a microchannel distillation (MCD) apparatus for ¹³⁶Xe enrichment. The relative volatilities, saturation vapor pressures, and enthalpies of vaporization of the nine Xe isotopes were determined, and a corresponding pseudo-component model was validated in Aspen Hyprotech Systems (HYSYS). A ternary model was then used to optimize the MCD parameters, identifying the optimal operating pressure, reflux ratio, and feed-to-product ratio effects on enrichment efficiency and reboiler power consumption. Subsequent optimization via uniform design, stepwise quadratic regression, non-dominated sorting genetic algorithm (NSGA)-Ⅲ, and the technique for order preference by similarity to an ideal solution (TOPSIS) reduced power consumption while increasing ¹³⁶Xe abundance from 8.670% to 13.347%. This microchannel cascaded distillation system overcomes conventional limitations and offers a novel and efficient approach for ¹³⁶Xe enrichment with significant theoretical and practical implications.