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The possibility of removal of pharmaceutically active substances, atenolol, diclofenac sodium and salicylic acid, from water solutions using hierarchical form of zeolite ZSM-5 is investigated in this paper. Mesopore formation in ZSM-5 was achieved using alkaline treatment. Zeolitic samples were characterized by X-ray diffraction, low temperature nitrogen adsorption, solid-state 27Al MAS NMR, point of zero charge determination and microcalorimetry – volumetry of ammonia adsorption. Adsorption isotherms of pharmaceutically active substances were obtained and liquid calorimetric experiments were used to evaluate the strength of interactions. The capacity for salicylic acid adsorption measured for the mesoporous sample did not significantly differ from the results obtained for the parent ZSM-5. However, in the case of atenolol and diclofenac sodium, mesoporous ZSM-5 exhibited increased adsorption capacities. Calorimetric data revealed higher heats of atenolol adsorption on mesoporous ZSM-5, compared to the parent. Based on similar acidity and surface charge determined for the two samples, our results show that geometry and dimensions of both zeolite pores and adsorbing molecules play a crucial role in the studied adsorption processes and that tailoring ZSM-5 porosity by desilication can be used to expand its applicability in depollution processes. Keywords: Hierarchical ZSM-5, Pharmaceutically active compounds, Adsorption, Liquid calorimetry

The microstructure of the starting hydrogel has extremely important role in the synthesis of the microporous materials. Due to the fact that very limited number of experimental methods (techniques) can be used for gel analysis, there are still a lot of missing informations about the processes on molecular level, which occur before and during the nuclei formation. In this paper, various methods were used in characterization of pretreated (aged) hydrogel before the process of its hydrothermal transformation to zeolite A. Results show the changes in chemical composition and in microstructure of the solid phase (FTIR, PALS, BET, DTG), indicating that the structure of the ordered phase (potential nuclei) within gel matrix (completely amorphous according to PXRD patterns) is rather of different structural units typical for FAU and SOD (or their mixture) than the final product (LTA) only!