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This paper presents isotherm results and basic (ΔH, ΔF and ΔS) thermodynamic characteristics of methanol adsorption in Cu2+ZSM-5 zeolite. The trinomial equation of adsorption isotherm by the bulk micropore filling theory (VMOT) is also described. A correlation between adsorption-energy characteristics was found and molecular mechanisms of methanol adsorption in Cu2+ZSM-5 zeolite were revealed in the whole filling region. It was determined that Cu2+ cations are located in shielded positions of the crystal lattice of zeolite ZSM-5. Adsorption of methanol molecule leads to the migration of Cu2+ cations from the zeolite lattice to the crossings formed by the intersection of straight and zigzag channels and to the formation of ion/molecular complexes of different multiplicity in them. It was found that small polar methanol molecules form high-energy hepta complexes with Cu2+ cation and are located in the first coordination sphere in Cu2+ZSM-5 zeolite. It was determined that the average molar entropy (-65 kJ/mol) of methanol adsorption indicates that in the zeolite the mobility of methanol molecules is lower than the liquid phase and close to the mobility of the solid phase.

This paper presents the results of isotherm and basic (ΔH, ΔF, and ΔS) thermodynamic characteristics of ammonia adsorption in Na zeolites2,87 ZSM-5 and Li3,37 ZSM-5; also the adsorption isotherm is described by the bulk micro-pore filling theory (BFM) equations. The correlation between adsorption-energy characteristics is found, and the molecular mechanism of ammonia adsorption in Na2,87ZSM-5 and Li3,37ZSM-5 zeolites in the whole filling region is revealed. The ammonia adsorbed in NaZSM-5 and LiZSM-5 zeolites is located in the first coordination sphere with Na+ and Li+ cations, forming octa- and hexaammonia complexes. From the adsorption thermokinetics, it was determined that Li+ cations are located in the screened positions of the ZSM-5 zeolite crystal lattice. The adsorption of ammonia molecule results in Li+ cations migration from the zeolite lattice into junctions formed by the intersection of straight and zigzag channels and the formation of ion/molecular complexes of various multiplicity in them. It was determined that the average molar entropy of ammonia adsorption on NaZSM-5 and LiZSM-5 zeolites indicates that the mobility of ammonia molecules in the zeolite is below the liquid phase and close to the mobility of the solid phase, indicating a strong limitation of mobility of ammonia adsorbed on the cations.