There is great interest in adsorptive separation of light olefins from alkanes with the same carbon number. However, previous investigations mainly focused on binary olefin/alkane mixtures or always produced mixed olefin from multiple components. Adsorptive separation of single-component olefins from mixtures containing multiple olefins is of practical importance but still a big challenge in industry. Present work provides an approach to the successive separation of C₃H₆ and C₂H₄ from a mixture of C₂H₄/C₂H₆/C₃H₆/C₃H₈ using tandem twin fixed beds filled with two well-regulated zeolites LTA. The adsorbents of Ni-5A and Ag/Cd-4A were post-synthesized via low transition-metal doping into zeolites LTA and employed to separate the C₃H₆ and C₂H₄ from the quaternary mixture. The Ni-5A attains a C₃H₆ uptake of 2.25 mmol/g and a C₃H₆/C₂H₄ Henry selectivity of 10.4, while the Ag/Cd-4A exhibits a C₂H₄ adsorption capacity of 3 mmol/g and a C₂H₄/C₂H₆ Henry selectivity of 1015.5. Furthermore, the molecule sieving of C₂H₄ is mainly determined by the micropore size of adsorbent, and the selective adsorption of C₃H₆ over C₂H₄ is largely attributed to the strong guest – host interactions with the metal sites. In addition, both the Ag/Cd-4A and Ni-5A adsorption beds can be well desorbed via CO₂ purging. The DFT calculations reveal the molecular deformation of C₂H₄ and C₃H₆ during passing through the 8MR of Ag/Cd-4A and the competitive adsorption affinity of Ni-5A towards C₃H₆. The present process of tandem fixed beds coupled with well-regulated zeolite adsorbents provide an efficient strategy for the adsorptive separation of the mixtures of olefins and alkanes.

人们对从具有相同碳数的烷烃中吸附分离轻质烯烃很感兴趣。然而，以前的研究主要集中在二元烯烃/烷烃混合物或总是由多种组分生产混合烯烃。从含有多种烯烃的混合物中吸附分离单组分烯烃具有实际重要性，但仍然是工业中的一大挑战。_{目前的工作提供了一种从 C 2} H ₄ /C ₂ H 6 _/ C ₃ H ₆ /C ₃ H ₈混合物中连续分离C 3 H ₆和_{C 2 H 4}的方法使用串联双固定床填充两种良好调节的LTA沸石。Ni-5A和Ag/Cd-4A吸附剂通过低过渡金属掺杂到LTA沸石中后合成，并用于从四元混合物中分离C ₃ H ₆和C ₂ H _{4 。}Ni-5A的C ₃ H ₆吸收量为2.25 mmol/g，C ₃ H ₆ /C ₂ H ₄ Henry选择性为10.4，而Ag/Cd-4A的C ₂ H ₄吸附容量为3 mmol /g 和 C ₂ H ₄ /C ₂ H ₆亨利选择性为1015.5。_{此外，C 2} H ₄的分子筛分主要取决于吸附剂的微孔尺寸，而C ₃ H ₆相对于C ₂ H ₄的选择性吸附很大程度上归因于与金属位点的强客主相互作用。此外，Ag/Cd-4A和Ni-5A吸附床均可以通过CO ₂吹扫得到良好的解吸。DFT计算揭示了C ₂ H ₄和C ₃ H ₆在通过Ag/Cd-4A的8MR过程中的分子变形以及Ni-5A对C ₃ H的竞争吸附亲和力₆ . 本发明的串联固定床与调节良好的沸石吸附剂相结合的工艺为烯烃和烷烃混合物的吸附分离提供了有效的策略。