Volavšek Janez, Pliekhov Oleksii, Pliekhova Olena, Mali Gregor, Zabukovec Logar Nataša
National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia.
Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia.
Nanomaterials (Basel). 2022 Apr 14;12(8):1352. doi: 10.3390/nano12081352.
The present work deals with the study of water adsorption on acid-modified zeolites A. Commercial zeolites 4A (Na form) and 5A (Ca form) were subjected to EDTA dealumination, and their structure, textural properties and stability were checked by XRD, EDX, NMR and N physisorption analyses. The water adsorption isotherms of the parent zeolites and their modified forms were measured at a temperature of 25 °C and up to a relative pressure of 0.9. The results show that the treatment with EDTA drastically changes the structural properties of the zeolites and increases the water adsorption capacity by up to 10%. The changes depend on the type of extra-framework cations (Na and Ca) and the EDTA concentration.
本研究工作涉及对酸改性A型沸石上水吸附的研究。将商用4A（钠型）和5A（钙型）沸石进行EDTA脱铝处理，并通过XRD、EDX、NMR和N物理吸附分析对其结构、织构性质和稳定性进行了检测。在25℃温度下直至相对压力为0.9，测定了原始沸石及其改性形式的水吸附等温线。结果表明，用EDTA处理会显著改变沸石的结构性质，并使水吸附容量提高多达10%。这些变化取决于骨架外阳离子（Na和Ca）的类型以及EDTA浓度。
