Single pellet reactor for the dynamic analysis of gas-solid reactions ''reaction of SO2 with activated soda''

Kopac, T
Dogu, G
Doğu, Timur
Single-pellet moment technique which was initially proposed for the measurement of effective diffusivities in porous catalysts and adsorption rate and equilibrium constants was modified for the analysis of gas-solid reactions. In this technique dynamic version of the Wicke-Kallenbach single-pellet cell was used A pulse of a tracer gas was introduced into stream flowing over one end face of the pellet. In the modified pulse-double response procedure, experimental moments of the response peaks of both reactant and product Bases measured in both top and bottom outlet streams of the single-pellet reader wee used for the evaluation of intrapellet rate and equilibrium parameters. Application of the technique to the reaction of SO2 with activated soda indicated that the value of while modulus decreased from 6.74 to 0.33 by the increase of fractional conversion of Na2CO3 to Na2SO3 from zero to 0.63. In this range of conversion values a significant variation in pore structure and also a decrease of effective diffusivity of SO2 from 0.045 cm(2)/s to 0.025 cm(2)/s was observed. A cell model which considered the changes in pore length and radius with reaction extent and variations in product lays diffusion resistance was shown to be successfully used in the analysis of experimental observations. A review of single-pellet dynamic reader studies for catalytic and noncatalytic gas-solid reactions was also given.


One-sided single-pellet technique for adsorption and intraparticle diffusion
Doğu, Timur; Dogu, G; McCoy, BJ; Smith, JM (1996-02-01)
The one-sided single-pellet dynamic technique introduced in this article is shown to be a very effective and simple method for the analysis of adsorption and diffusion in porous solids. Moment expressions are presented for reversible and irreversible adsorption processes. Since the adsorption equilibrium constant is the only unknown parameter in the first moment expression, this parameter can be evaluated from a single set of pulse-response experiments. This technique to evaluate the adsorption equilibrium ...
A moment technique for adsorption rate on metal surfaces of supported catalysts CO adsorption on Pt-Al2O3 washcoated monolith
Dogu, G; Ozkan, G; Doğu, Timur (2001-12-15)
A moment technique was developed for the investigation of adsorption on metal surfaces of supported catalysts. The technique was applied to the evaluation of adsorption rate parameters of CO on a Pt-Al2O3 washcoated monolith. The adsorption rate constants evaluated in the temperature range 273-316 K showed significant decrease with an increase in surface coverage. Results of pulse response experiments corresponding to zero coverage gave the apparent activation energy for adsorption as 21 kJ/mol. This method...
Low level NO gas sensing properties of Cu doped ZnO thin films prepared by SILAR method
Corlu, T.; Karaduman, I.; Galioglu, S.; Akata Kurç, Burcu; YILDIRIM, MEMET ALİ; ATEŞ, AYTÜNÇ; ACAR, SELİM (2018-02-01)
We report the successful synthesis and characterization of Zn1-xCuxO (x = 0.05, 0.10, 0.15, 0.20) thin films prepared by a simple and facile Successive Ionic Layer Adsorption and Reaction (SILAR) method. The nitrogen monoxide (NO) gas sensing properties of the Zn1-xCuxO sensors were studied systematically. The sensors were proved to have acceptable responses towards 20 ppb NO gas. Zn0.90Cu0.10O exhibited improved sensing performance at operating temperature of 55 degrees C compared to other samples. To impr...
Non-equilibrium molecular dynamics simulation of electromigration in aluminum-based metallic interconnects
Şen, Fatih Gürçaǧ; Aydınol, Mehmet Kadri (2006-12-01)
The effect of alloying elements in aluminum on diffusion behavior was investigated using non-equilibrium molecular dynamics (NEMD) under the effect of electromigration wind force. The electromigration wind force was computed based on a theory using the pseudopotential formalism of the elements, where it depends on the type and distribution of the imperfections in the lattice. It was found that the electromigration force on the impurity depends on the scattering power of the atom, which is related to the che...
Diffusion Resistances and Contribution of Surface Diffusion in TAME and TAEE Production Using Amberlyst-15
Doğu, Timur; Boz, Nezahat; MÜRTEZAOĞLU, KIRALİ; DOĞU, GÜLŞEN (2003-01-01)
Effective diffusivities and adsorption equilibrium constants of methanol, ethanol and 2-methyl-2-butene (2M2B), in Amberlyst 15, were evaluated from batch adsorption experiments. Moment expressions derived for different models involving diffusion resistances in the macropores and within the gel-like micrograins were used for the evaluation of effective diffusion coefficients. Contribution of surface diffusion to diffusion flux within the macropores was found to be quite significant. Also, it was found that ...
Citation Formats
T. Kopac, G. Dogu, and T. Doğu, “Single pellet reactor for the dynamic analysis of gas-solid reactions ″reaction of SO2 with activated soda″,” CHEMICAL ENGINEERING SCIENCE, pp. 2201–2209, 1996, Accessed: 00, 2020. [Online]. Available: