Sorption of Sulfur Dioxide on Hydrogen Form and Aluminum-Deficient Mordenites

The SO 2 sorption characteristics of a commercial H-mordenite and an aluminum-deficient mordenite with a molar SiO 2 /Al 2 O 3 ratio of 75, prepared from the H-form, were investigated. The sorption isotherms and the reduced sorptive diffusivities were determined in the temperature range 298-358 K and at pressures up to 0.2 atm. It was found that the partially irreversible SO 2 sorption on the H-form became completely reversible by the removal of structural aluminum, while the absolute sorption capacity was decreased by 10-40% and the rate of sorption was improved by 50%.