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This paper presents the results obtained by adsorption-calorimetric method of isotherms and basic (ΔH, ΔF and ΔS) thermodynamic characteristics of ammonia adsorption in Cs3,17ZSM-5 zeolite, also the adsorption isotherm described by the equations of the volume filling theory of micropores (TFSM). For measurements of isotherms and differential heat of adsorption, a system consisting of a universal high-vacuum adsorption unit and a coupled differential modified Tian-Calvet type microcalorimeter, DAK-1-1A, was used which directly quantifies and qualifies the nature and forces of adsorption interaction. The correlation between the adsorption-energy characteristics is found and the molecular mechanism of ammonia adsorption in Cs3,17ZSM-5 zeolite in the whole filling region is revealed. Ammonia adsorbed in the Cs3,17ZSM-5 zeolite is located in the first coordination sphere with the Cs+ cation, forming penta-ammonia complexes. It is determined that the average molar entropy of ammonia adsorption on the Cs3,17ZSM-5 zeolite, indicates that in the zeolite the mobility of ammonia molecules is below the liquid phase and close to the mobility of the solid phase, indicating a strong limitation of mobility of ammonia adsorbed on cations. [ABSTRACT FROM AUTHOR]

Carbon dioxide is a strategic gas in many industrial processes. Large amounts of carbon dioxide are emitted into the atmosphere leading to global environmental problems. It is a product of combustion and a greenhouse gas; capturing it for reuse is a major problem facing our society today. One way to recover carbon dioxide is to use an adsorption process. Zeolites are a potential material for the selective adsorption and separation of carbon dioxide. Zeolites are of great interest because of their ability to change their properties, both textural and chemical, which ultimately affect the adsorption properties of zeolites. This paper presents the results of a study of isotherms and basic thermodynamic characteristics of carbon dioxide adsorption on zeolites like ZSM-5. The adsorption isotherm is also described by the equations of the theory of volume filling of micropores (VMOT). [ABSTRACT FROM AUTHOR]