Adsorptive separation is a promising alternative to the energy-intensive cryogenic distillation process for separating the ethane/ethylene (C₂H₆/C₂H₄) mixtures. Herein, two pillared-layer metal-organic frameworks (MOFs), Ni(HBTC)(bipy) and Ni₂(HBTC)₂(bipy)_0.6(dabco)_1.4, are prepared as the C₂H₆-selective adsorbents for C₂H₄ purification from C₂H₆/C₂H₄ mixtures. The effect of the type of pillars on the framework structure, thermal and moisture stability, as well as the C₂H₆ and C₂H₄ adsorption propertiy, of the MOFs was studied. The use of the longer pillars (i.e. bipy versus dabco) to scafolld the Ni(HBTC) improved the pore size (5.5 Å versus 5.3 Å), specific surface area (1,474 m²/g versus 1,070 m²/g) and moisture stability in the relative humidity range of 0–90%, but compromised the thermal stability (267 °C versus 278 °C). Both MOFs were C₂H₆-selective, which was evidencd by the single component adsorption experiments using C₂H₆ and C₂H₄. The ideal adsorbed solution theory (IAST) selectivity for C₂H₆/C₂H₄ mixtures (1:1 and 1:15, v/v) is in the range of 1.4–1.7 at 25–50 °C and 0–1 bar. The preferential adsorption towards C₂H₆ over C₂H₄ on both MOFs is then explained by the isosteric heat of adsorption. Additionally, Ni(HBTC)(bipy) also shows the best capacity of up to 6.6 mmol/g for C₂H₆ adsorption in comparison with other C₂H₆-selective MOFs at 25 °C and 1 bar. Both MOFs showed the excellent recyclability, with the negligible reduction in the gas uptake observed during four cycles of adsorption/desorption tests. Besides, breakthrough experiments demonstrated that both MOFs can achieve efficient separation of an equimolar C₂H₆/C₂H₄ mixture. The findings suggest that Ni(HBTC)(bipy) and Ni₂(HBTC)₂(bipy)_0.6(dabco)_1.4 can be further considered as C₂H₆-trapping adsorbents for the C₂H₆/C₂H₄ separation applications in practice.

吸附分离是一种用于分离乙烷/乙烯（C ₂ H ₆ / C ₂ H ₄）混合物的高能耗低温蒸馏方法的有前途的替代方法。在此，制备两个柱状层金属有机骨架（MOF），即Ni（HBTC）（bipy）和Ni ₂（HBTC）₂（bipy）_0.6（dabco）_1.4，作为对C的C ₂ H ₆选择性吸附剂。₂ ħ ₄选自C纯化₂ ħ ₆ / C ₂ H ^ ₄混合物。研究了支柱类型对MOFs骨架结构，热稳定性和湿气稳定性以及C ₂ H ₆和C ₂ H ₄吸附性能的影响。使用时间越长支柱（即联吡啶与DABCO）到scafolld镍（HBTC）改善了孔的尺寸（5.5埃与5.3埃），比表面积（1474米² / g的与1070米² / g）和水分稳定性在相对湿度0-90％的范围内，但损害了热稳定性（267°C对278°C）。两个MOF均为C ₂ H ₆-选择性的，这是通过使用C ₂ H ₆和C ₂ H ₄的单组分吸附实验证明的。对于C ₂ H ₆ / C ₂ H ₄混合物（1：1和1：15，v / v），理想的吸附溶液理论（IAST）选择性在25–50°C和0–0的范围内为1.4–1.7 1巴。然后通过等规吸附热来解释两个MOF相对于C ₂ H _4相对于C ₂ H ₆的优先吸附。此外，Ni（HBTC）（bipy）对C ₂ H的最佳吸附量也高达6.6 mmol / g₆吸附在与其它的C比较₂ ħ ₆在25℃和1巴-选择性的MOF。两种MOF均显示出优异的可回收性，在四个吸附/解吸测试循环中观察到的气体吸收量可忽略不计。此外，突破性实验表明，两种MOF均可实现等摩尔C ₂ H ₆ / C ₂ H ₄混合物的有效分离。这一发现表明，镍（HBTC）（联吡啶）和Ni ₂（HBTC）₂（联吡啶）_0.6（DABCO）_1.4可以进一步视为c ^ ₂ ^ h _6个-trapping吸附剂为C ₂H ₆ / C ₂ H ₄分离的实际应用。