关键词: 模拟移动床, 吸附分离, 5A分子筛, 吸附平衡常数, 正构烷烃

Abstract: Under the conditions of an adsorption temperature of 140 ℃ and an adsorption pressure of 2.0 MPa, the static adsorption method was employed to investigate the saturated adsorption capacity and adsorption equilibrium constants of different concentrations of C₅–C₉ n-paraffins on the adsorbent. The dynamic breakthrough curve method was used for data fitting to obtain the mass transfer coefficients of each component on the adsorbent. Based on these parameters, a n-C₅ and n-C₆ adsorption pulse test model was established. The model was validated through multi-component pulse experiments, with relative deviations between simulated and experimental values being less than 3%, indicating the reliability of both the model and the regressed parameters. Finally, an adsorption separation process model for C₅ and C₆ n-paraffins was developed to examine the effect of different numbers of adsorption beds on separation performance. The results show that the separation performance improves as the number of beds increases. However, when the number of beds reaches 12 or more, the improvement in separation performance becomes relatively small. Considering both investment costs and operational convenience, the optimal number of beds was determined to be 12.

Key words: simulated moving bed, adsorptive separation, 5A molecular sieve, adsorption equilibrium constant, n-paraffin