Three valsartan metal (tin, nickel, and magnesium) complexes were examined as capture and storage media for methane under high temperature (323 K) and pressure (50 bar) conditions. The surface morphology of the complexes were examined using Field emission scanning electron microscopy and displayed porous structures comprising particles of different shapes and sizes. The narrow pore-size distribution of metal complexes makes them suitable materials for methane capture. The methane adsorption–desorption isotherms of the metal complexes were reversible. The tin(IV) and nickel(II) complexes exhibited type-III physisorption isotherms, while the magnesium(II) complex displayed a type-IV physisorption isotherm. Both types of isotherms are typical for mesoporous materials. The magnesium(II) complex was more efficient compared with the tin(IV) and nickel(II) complexes. It exhibited a remarkable methane uptake capacity of 71.68 cm³/g under optimized conditions.

中文翻译：

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缬沙坦金属络合物作为甲烷的捕获和可逆存储介质

在高温（323 K）和压力（50 bar）条件下，对三种缬沙坦金属（锡，镍和镁）络合物作为甲烷的捕获和储存介质进行了研究。使用场发射扫描电子显微镜检查复合物的表面形态，并显示包含不同形状和大小的颗粒的多孔结构。金属络合物的孔径分布狭窄，使其成为甲烷捕获的合适材料。金属配合物的甲烷吸附-解吸等温线是可逆的。锡（IV）和镍（II）配合物表现出III型物理吸附等温线，而镁（II）配合物表现出IV型物理吸附等温线。两种等温线都是介孔材料的典型特征。与锡（IV）和镍（II）配合物相比，镁（II）配合物效率更高。甲烷吸收能力高达71.68厘米在优化条件下为³ / g。