Alteration of adsorption properties and porous structure (texture) of the KNaLSX zeolite at the initial stages of its destruction during ion-exchange modification in solutions of NH4Cl and thermal shock under vacuum degassing has been studied. Transmission electron microscopy, X-ray diffraction, low-temperature nitrogen adsorption and adsorption of CO2 and CH4 at 273 K were applied for characterization of the obtained materials. Conversion of the predominantly microporous material to the material with threemode pore-size distribution is shown. Significant fraction of the faujasite phase and corresponding micropores are preserved in the material. This is accompanied with formation of pores of two types: quasi-spherical mesopores with the characteristic size of 5 nm and the meso-macropores with typical size exceeding 40 nm. Basing on the obtained results, a mechanism of textural changes in the LSX zeolite treated under applied conditions is proposed.
|Журнал||Protection of Metals and Physical Chemistry of Surfaces|
|Состояние||Опубликовано - 1 ноя 2017|