An analysis of elementary processes of water desorption from zeolites of type a

Adsorption of nitrogen-oxygen mixture in NaCaA zeolites by elution chromatography

“…This behavior is reflected in the decreasing 2, 2/ 2, and ( 2) with little effect on oxygen adsorption as seen in Figures 4 and 5 particularly at presorption levels above 1 mmol/g. From desorption studies of water from zeolite A having monovalent and divalent cations (Vucelic et al, 1976; Dondur et al, 1976), three desorption peaks were reported. The first two peaks corresponding to low energy (AH = 56.5 and 60.6 kJ/mol) have been attributed to water desorption from the a-cage whereas the high-energy (AH = 125.5 kJ/mol) third peak has been ascribed to water desorption from the 8-cage of the zeolite.…”

Application of model-free kinetic analysis methods to dehydration of a HEU-type zeolite rich tuff from Turkey

“…Numerous studies of the dehydration kinetics of synthetic zeolites have been reported in the literature. The complex DSC curves of water desorption from NaA, LiA and KA zeolites were resolved into elementary curves using a computer program and the activation energies and transition temperatures for binding of water to the zeolites with three different phases were determined (Vucelić et al, 1976). Following a similar procedure for dehydration of NaA, LiA, KA, CdA, ZnA, MgA and CaA zeolites, the activation energy corresponding to the middle desorption peak was found to be in the range 37À46 kJ/mol using the Redhead method (Dondur & Vučelić, 1983a).…”