一种具有高CO吸附容量和高CO/N2及CO/CO2分离选择性的CuCl@β吸附剂

研制了一种新型的CuCl@β分子筛吸附剂材料,它不仅对CO有着高吸附容量,而且对CO/N₂和CO/CO₂的二元混合气有着高吸附选择性。利用自发单层分散的原理制备了一系列的CuCl@β分子筛材料,分别应用氮气吸附以及XRD进行表征。CO在CuCl@β分子筛上吸附等温线和动态透过曲线分别通过静态吸附和固定床实验获得。依据IAST理论模型计算了CuCl@β分子筛对CO/N₂二元混合物和CO/CO₂二元混合物的吸附选择性。研究结果表明:(1)氯化亚铜的负载增强了一氧化碳在CuCl@β分子筛上的吸附容量,其最佳负载量为0.4 g·g^-1。(2)CuCl@β分子筛吸附剂在增强CO的吸附量的同时,还降低了对二氧化碳和氮气的吸附。由于Cu⁺-CO π位络合键的存在,提高了CuCl@β分子筛对二元混合物CO/N₂和CO/CO₂的吸附选择性。(3)在低压下(0～10 kPa)下0.4CuCl@β分子筛对CO/N₂和CO/CO₂的吸附选择性分别高达1600～5200和120～370,远大于原始的β分子筛。CuCl@β分子筛对CO有着超高吸附容量以及吸附选择性,将会是一种很有潜力的CO分离提纯材料。

An efficient CuCl@β adsorbent with high CO adsorption uptake and CO/N2 and CO/CO2 selectivities

A novel CuCl@β zeolite with high CO capacity and high-selectivity for CO/N₂ and CO/CO₂ mixtures was developed. A series of CuCl@β zeolites were prepared by an auto single-layer dispersion method. The CuCl@βzeolites were characterized by N₂ adsorption and XRD. The adsorption isotherms and dynamic breakthrough curves of CO on the adsorbents were measured separately by a static adsorption and fixed-bed experiments. The adsorption selectivities of CuCl@β zeolite for CO/N₂ and CO/CO₂ mixtures were estimated on the basis of ideal adsorbed solution theory (IAST). The results showed that (a) the loading of CuCl onto β zeolite significantly enhanced CO adsorption capacity of the resulting CuCl@β adsorbent and the CuCl loading was optimized to be 0.4. (b) it not only significantly enhanced CO uptake, but also weakened N₂ and CO₂ adsorption on the CuCl@β adsorbents. As a result, it significantly enhanced CO/N₂ and CO/CO₂ selectivities of the adsorbent further, which can be attributed to the mild Cu⁺-CO interaction by π-complexation bond. (c) the 0.4CuCl@β adsorbent achieved a superior adsorption selectivity up to 1600-5200 and 120-370 at low pressure range of 0-10 kPa for CO/N₂ and CO/CO₂ mixtures, much higher than parent β zeolite. The high CO adsorption capacity and selectivity of CuCl@β adsorbents made it a promising adsorbent for CO/N₂ and CO/CO₂ separation.