Hydrothermal and alkaline stability of high-silica Y zeolites generated by combining substitution and steaming

Y-type zeolites dealuminated by steaming (DAY-T) are more stable in water and alkaline solutions than those dealuminated by substitution (DAY-S). However. DAY-S zeolites have a higher adsorption capacity and are more hydrophobic. A dealumination by substitution and subsequent steaming yields a zeolite DAY-ST that combines the high chemical stability of DAY-T with the high adsorption capacity and hydrophobicity of DAY-S.