Sorption of Methane and Nitrogen on Cesium Exchanged Zeolite-X: Structure, Cation Position and Adsorption Relationship

Abstract

The equilibrium adsorption study of methane and nitrogen on zeolite-X exchanged with different percentages of cesium ions was carried out using volumetric gas adsorption method. The dynamic breakthrough measurements were carried out using a fixed bed breakthrough reactor and binary (methane + nitrogen) gas mixture. The cesium ion exchanged zeolite samples were characterized by Brunauer–Emmett–Teller measurements, X-ray diffraction, scanning electron microscopy, and inductive coupled plasma-optical emission spectrophotometer analysis. Methane and nitrogen adsorption capacities depend on the percentage and position of cesium ions in the zeolite. The adsorption properties of ion exchanged zeolite were studied in correlation with cesium ion positions in the zeolite. Above 36% cesium ion exchange in NaX the methane adsorption capacity increases, while nitrogen adsorption capacity decreases. The cesium exchanged zeolite showed methane adsorption capacity of 21.1 molecules/(unit cell) and methane selectivity ove...