The propylene/propane separation properties of levyne zeolites with different framework Si/Al and Fe/Al ratios have been examined and compared with those of the four well-studied zeolite adsorbents (i.e., Na-A, Ca-A, Na-X and ITQ-12) for this separation. Both zeolite framework structure and composition were found to be critical for the propylene uptake, kinetic separation and adsorbent durability. Among the zeolites studied here, the mixed CaNH₄ form of a ferroaluminosilcate levyne (Si/Al = 15.5 and Fe/Al = 0.27) showed the highest propylene/propane selectivity (11). Under vacuum-swing adsorption mode at 298 K and reservoir pressure of 1.2 bar, this partially iron-substituted zeolite was characterized by a higher propylene uptake (ca. 1.0 vs 0.7 mmol g⁻¹) than its aluminosilicate version, which can be attributed to a combination of the molecular sieve effect of its framework topology and relatively weaker acidity. The results of this study demonstrate that, in contrast to widely held belief, zeolite adsorbents selective for propylene/propane separation do not need to be a pure-silica composition.

研究了具有不同骨架Si / Al和Fe / Al比的左炔烃的丙烯/丙烷分离性能，并将其与四种研究充分的沸石吸附剂（即Na-A，Ca-A，Na-X和Na-X）进行了比较。 ITQ-12）。发现沸石骨架结构和组成对于丙烯的吸收，动力学分离和吸附剂耐久性都是至关重要的。在这里研究的沸石中，铝铝硅酸铁炔的混合CaNH ₄形式（Si / Al = 15.5和Fe / Al = 0.27）显示出最高的丙烯/丙烷选择性（11）。在298 K的真空摆动吸附模式和1.2 bar的储层压力下，这种部分铁取代的沸石的特征在于较高的丙烯吸收（约1.0对0.7 mmol g ^-1）相比其铝硅酸盐版本，这可以归因于其骨架拓扑的分子筛效应和相对较弱的酸度的组合。这项研究的结果表明，与公认的观点相反，对丙烯/丙烷分离具有选择性的沸石吸附剂不必是纯二氧化硅成分。