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19-P-06 - Modeling of sulfur dioxide breakthrough curves from ternary wet mixtures on MOR type zeolite
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1 9 - Diffusion: Fundamental Approach (Tuesday) 19-P-06 - Modeling of sulfur dioxide breakthrough curves from ternary wet mixtures on MOR type zeolite M. Mello a, M. Eid a, S. Ho(,evarb and U. Lavren6i~-Stangarb
aDepartment of Chemical Engineering, University of New Brunswick, P.O. Box 4400, Fredericton, N.B., Canada E3B 5A3 ([email protected]); bNational Institute of Chemistry, Laboratory of Catalysis and Reaction Engineering, Hajdrihova 19, 61115 Ljublj'ana, Slovenia The adsorption of SO2 from temary mixtures with water and CO2 on high silica MOR zeolite was investigated using the breakthrough curve method. The breakthrough model was based on axially dispersed plug flow through the column, and mixture equilibrium was described by Langmuir 1 extended model. The solution was obtained by finite element collocation method using the commercial software gPROMS. Infra-red spectroscopic measurements gave further evidence that water was more strongly adsorbed than SO2, thus displacing it and causing rollup effect.
19-P-07- The diffusion and sorption dynamics of acetylene in zeolites G. Onyestydk (a), J. Valyon (a) and L.V.C. Rees (b)
a Institute of Chemistry, Chemical Research Center, Hungarian Academy of Sciences valyon@cric, chemres, hu, Hungary b Department of Chemistry, University of Edinburgh, Edinburgh, United Kingdom Species formed from acetylene (Ay) adsorbed in zeolite Y, mordenite, beta and ZSM-5 have been studied by IR spectroscopy. The dynamics of Ay physisorption has been characterized by the frequency response method (FR). The rate of micropore diffusion governed the transport in Na-mordenite, while sorption was the rate limiting process step for all the Hzeolites. The equilibrium constants (Ka) of Ay sorption have been determined applying the Langmuir rate equation to describe the pressure dependence of the sorption time constants. The n-octane hydroconversion activity of Pt/H-zeolites was found to increase linearly with the Ka of Ay sorption on the H-zeolites.
19-P-08 -Transient uptake measurements using an oscillating microbalance: effect of acid leaching on the diffusivity of n-hexane in Pt/Hmordenite S. van Donk, A. Broersma, O.L.J. Gijzeman, J.H. Bitter and K.P. de Jong*
Department of Inorganic Chemistry and Catalysis, Debye Institute, Utrecht University, The Netherlands; *Corresponding author, e-mail: [email protected] Measurements performed in a tapered element oscillating microbalance (TEOM) reveal that diffusivities can be derived from uptake data monitored under full reaction conditions. In this way the effect of acid leaching on the diffusional behaviour of n-hexane in Pt/H-Mordenite is investigated. It is shown that acid leaching largely enhances the n-hexane uptake rate, but does not result in a net increase in the intracrystalline steady state diffusivity. It is concluded that the accelerated uptake after acid leaching merely arises from the shorter intracrystalline diffusion path resulting from the mesoporous structure.
1 9 - Diffusion: Fundamental Approach (Tuesday) 19-P-06 - Modeling of sulfur dioxide breakthrough curves from ternary wet mixtures on MOR type zeolite M. Mello a, M. Eid a, S. Ho(,evarb and U. Lavren6i~-Stangarb
aDepartment of Chemical Engineering, University of New Brunswick, P.O. Box 4400, Fredericton, N.B., Canada E3B 5A3 ([email protected]); bNational Institute of Chemistry, Laboratory of Catalysis and Reaction Engineering, Hajdrihova 19, 61115 Ljublj'ana, Slovenia The adsorption of SO2 from temary mixtures with water and CO2 on high silica MOR zeolite was investigated using the breakthrough curve method. The breakthrough model was based on axially dispersed plug flow through the column, and mixture equilibrium was described by Langmuir 1 extended model. The solution was obtained by finite element collocation method using the commercial software gPROMS. Infra-red spectroscopic measurements gave further evidence that water was more strongly adsorbed than SO2, thus displacing it and causing rollup effect.
19-P-07- The diffusion and sorption dynamics of acetylene in zeolites G. Onyestydk (a), J. Valyon (a) and L.V.C. Rees (b)
a Institute of Chemistry, Chemical Research Center, Hungarian Academy of Sciences valyon@cric, chemres, hu, Hungary b Department of Chemistry, University of Edinburgh, Edinburgh, United Kingdom Species formed from acetylene (Ay) adsorbed in zeolite Y, mordenite, beta and ZSM-5 have been studied by IR spectroscopy. The dynamics of Ay physisorption has been characterized by the frequency response method (FR). The rate of micropore diffusion governed the transport in Na-mordenite, while sorption was the rate limiting process step for all the Hzeolites. The equilibrium constants (Ka) of Ay sorption have been determined applying the Langmuir rate equation to describe the pressure dependence of the sorption time constants. The n-octane hydroconversion activity of Pt/H-zeolites was found to increase linearly with the Ka of Ay sorption on the H-zeolites.
19-P-08 -Transient uptake measurements using an oscillating microbalance: effect of acid leaching on the diffusivity of n-hexane in Pt/Hmordenite S. van Donk, A. Broersma, O.L.J. Gijzeman, J.H. Bitter and K.P. de Jong*
Department of Inorganic Chemistry and Catalysis, Debye Institute, Utrecht University, The Netherlands; *Corresponding author, e-mail: [email protected] Measurements performed in a tapered element oscillating microbalance (TEOM) reveal that diffusivities can be derived from uptake data monitored under full reaction conditions. In this way the effect of acid leaching on the diffusional behaviour of n-hexane in Pt/H-Mordenite is investigated. It is shown that acid leaching largely enhances the n-hexane uptake rate, but does not result in a net increase in the intracrystalline steady state diffusivity. It is concluded that the accelerated uptake after acid leaching merely arises from the shorter intracrystalline diffusion path resulting from the mesoporous structure.