Fontàs Clàudia, Vera Ruben, Anticó Enriqueta, Martínez de Yuso María Del Valle, Rodríguez-Castellón Enrique, Benavente Juana
Department of Chemistry, University of Girona, 17003 Girona, Spain.
Laboratorio de Espectroscopía de Rayos-X, Servicios Centrales de Apoyo a la Investigación de la Universidad de Málaga, 29071 Málaga, Spain.
Membranes (Basel). 2022 Feb 5;12(2):192. doi: 10.3390/membranes12020192.
Surface characterization of polymer inclusion membranes (PIMs) using the polymers cellulose triacetate and polyvinyl chloride, containing different ionic liquids (ILs) as carriers, has been performed. Three different ILs have been tested: commercial trioctyl methylammonium chloride (Aliquat 336-AlqCl) and two derivatives bearing the counter anion NO or SCN (AlqNO and AlqSCN, respectively). Surface analysis was performed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) for both dry membranes and PIMs immersed for 4 days in ultrapure water to investigate the effect of the interaction of water with the membrane's morphology and composition. XPS analysis of the PIMs revealed that immersion in ultrapure water causes a decrease in the atomic concentration percentage (A.C.%) of the specific IL atoms (Cl, S, and N) when compared with dry samples. Moreover, SEM images of the PIMs containing the IL AlqNO showed an alteration in the morphology of the membrane due to water contact at surface level, whereas no changes were observed at a bulk level. These changes in the surface composition of the water equilibrated PIMs may be associated with the solubilization of the IL in the water solution, which, therefore, may affect the reactivity of the membrane's surface. To better understand this effect, PIMs containing both AlqCl and AlqNO as carriers were used for arsenic (V) transport. It was found that AlqCl was the most effective IL and that the effectivity of the PIM on As(V) removal was not affected after five cycles of the membrane's reuse.
使用三醋酸纤维素和聚氯乙烯作为聚合物，包含不同离子液体（ILs）作为载体，对聚合物包合物膜（PIMs）进行了表面表征。测试了三种不同的离子液体：市售的三辛基甲基氯化铵（Aliquat 336 - AlqCl）以及两种带有抗衡阴离子NO或SCN的衍生物（分别为AlqNO和AlqSCN）。通过扫描电子显微镜（SEM）和X射线光电子能谱（XPS）对干膜以及浸泡在超纯水中4天的PIMs进行表面分析，以研究水与膜的形态和组成相互作用的影响。对PIMs的XPS分析表明，与干燥样品相比，浸泡在超纯水中会导致特定离子液体原子（Cl、S和N）的原子浓度百分比（A.C.%）降低。此外，含有离子液体AlqNO的PIMs的SEM图像显示，由于表面水平的水接触，膜的形态发生了变化，而在整体水平上未观察到变化。水平衡后的PIMs表面组成的这些变化可能与离子液体在水溶液中的溶解有关，因此可能会影响膜表面的反应性。为了更好地理解这种影响，使用同时含有AlqCl和AlqNO作为载体的PIMs进行砷（V）的传输。结果发现AlqCl是最有效的离子液体，并且在膜重复使用五个循环后，PIMs对As（V）的去除效果不受影响。
