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The purpose of this study is to evaluate the dehydration kinetics of MxNa96-x-LSX (M = L+ Ca2+ and Ag+) zeolites and assess their potential for N-2/O-2 adsorption and selectivity using ideal adsorbed solution theory. In order to achieve our objective, MxNa96-x-LSX (M = Li+, Ca2+, and Ag+) zeolites were prepared via conventional ion exchange methods from Na-LSX zeolite. Meanwhile, their structural and textural properties were characterized by N-2 adsorption-desorption, TG-DTG, ICP-OES, XRD, FT-IR, EDS, elemental mapping and SEM techniques. The kinetics (activation energy, pre-exponential factor, and most probable mechanism/model) of dehydration process were investigated via Kissinger, Flynn-Wall-Ozawa and Coats-Redfern methods. The results show a strong dependence on the choice of mechanism function, which can help in proposing the best relevant kinetic model. Moreover, the results further reveal that Li+ and Ca2+ ions (which are inexpensive) in Li-LSX and Ca-LSX fill the low-energy sites SI, SI', SII, and SII' first and then SII and SIII' sites. Li-LSX and Ca-LSX hold comparative advantages, which suggest that they would be the most promising adsorbents for air separation and pure oxygen production by pressure swing adsorption. However, Ag-LSX presents superior performance at relatively low pressures. Therefore, the quantitative evaluation of kinetic parameters of dehydration is necessary to provide the theoretical principles in understanding N-2 and O-2 adsorption phenomena.
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