Investigation of sorption capacity of pumice for SO2 capture

The sorption capacity of pumice has been investigated for the removal of SO2 from binary and tertiary mixtures with N2 and N2 + CO2, respectively. The influence of the presence of water on the adsorption of SO2 has also been analyzed by moisturizing the adsorbent at different levels within the limits of applicability of Henry's law. SO2 adsorption capacity of dry pumice was found as 16.26 mg SO2 g−1 pumice while for adsorption on moisturized pumice (22 wt% moisture) it was 33.4 mg SO2 g−1 pumice at 293 ± 2 K. When co-adsorption of CO2 and SO2 was carried out SO2 adsorption on dry pumice was slightly reduced, but this counter effect of CO2 was gradually removed by increasing water content of the adsorbent. Moreover, the acidic character of the adsorption products reduced the durability of pumice when it was moisturized.