Developing porous adsorbents for the complete sieving of propylene/propane mixtures represents an alternative method to energy-intensive cryogenic distillation processes. However, the similar physical properties of these molecules and the inherent trade-off among adsorption capacity, selectivity, diffusion kinetic and host–guest binding interactions in molecular sieving adsorbents makes their separation challenging. Here we report the separation of propylene/propane mixtures through a crystalline porous material (HAF-1) that features channels and shrinkage throats—the latter defined as narrower channels that connect the main channels and a molecular pocket—where the throat aperture is between the kinetic diameters of propylene and propane. Single-crystal X-ray diffraction and computational simulation reveal that the shrinkage channels and hanging molecular pockets are key to ensure high sieving efficiency and high propylene adsorption capacity. Dynamic breakthrough experiments show that HAF-1 enables the achievement of high-purity (≥99.7%) propylene with a productivity of 33.9 l kg⁻¹ by just one adsorption–desorption circle from propylene/propane mixtures.

开发用于完全筛分丙烯/丙烷混合物的多孔吸附剂是能源密集型低温蒸馏工艺的替代方法。然而，这些分子的相似物理性质以及分子筛吸附剂中吸附能力、选择性、扩散动力学和主客体结合相互作用之间的固有权衡使它们的分离具有挑战性。在这里，我们报道了丙烯/丙烷混合物通过结晶多孔材料 （HAF-1） 的分离，该材料具有通道和收缩喉，后者定义为连接主通道和分子袋的较窄通道，其中喉孔位于丙烯和丙烷的动力学直径之间。单晶 X 射线衍射和计算模拟表明，收缩通道和悬挂的分子袋是确保高筛分效率和高丙烯吸附能力的关键。动态突破实验表明，HAF-1 只需从丙烯/丙烷混合物中进行一个吸附-解吸循环，即可获得高纯度 （≥99.7%） 丙烯，生产率为 33.9 l ^kg-1。