Positron annihilation lifetime spectroscopy (PALS) study of the influence of aluminosilicate gel ageing on its microstructure

► Zeolite precursor porosity was probed by positron annihilation lifetime spectroscopy. ► Sizes estimated from positron lifetimes correlate to the sizes of the zeolite A structural entities. ► Correlation of (quasi)crystalline phase amount and the positron lifetime intensity is assumed.