BREAKTHROUGH STUDY OF THE ADSORPTION AND SEPARATION OF SULFUR-DIOXIDEFROM WET GAS-USING HYDROPHOBIC ZEOLITES

The adsorptive and kinetic behaviour patterns of SO2 and water vapour on mordenites and pentasil zeolites were investigated using the breakt hrough curve method. For all the zeolites studied, the breakthrough ex perimental data show a decrease in the equilibrium capacities for both SO2 and H2O with increasing SiO2/Al2O3 ratio. At the lower ratios SO2 adsorption is believed to be influenced by the basicity of the zeolit e. The presence of water in the gas reduces its SO2 capacity to varyin g degrees, depending on the SiO2/Al2O3 ratio. In contrast, the presenc e of CO2 (in the wet SO2-containing gas) has very little effect. The h ydrophobic indices, which were used to interpret the selectivity of SO 2 adsorption, showed different trends with SiO2/Al2O3 ratios. The Lang muir-Freundlich and extended Langmuir-Freundlich equilibrium models we re used to predict equilibrium properties for the single-component and binary systems, respectively. The linear driving force-based non-isot hermal model was used to fit experimental breakthrough curves for the single-component systems. Overall mass transfer resistances derived fr om the model were compared with the values obtained for SO2 and water vapour adsorption in pelleted samples using a simplified biporous adso rbent model. Breakthrough curves for the binary systems were calculate d using kinetic and equilibrium data of the single-component systems.