| Summary: | The main goal of the study was the development of effective catalysts for the low-temperature selective catalytic reduction of NO with ammonia (NH<sub>3</sub>-SCR), based on ferrierite (FER) and its delaminated (ITQ-6) and silica-intercalated (ITQ-36) forms modified with copper. The copper exchange zeolitic samples, with the intended framework Si/Al ratio of 30 and 50, were synthetized and characterized with respect to their chemical composition (ICP-OES), structure (XRD), texture (low-temperature N<sub>2</sub> adsorption), form and aggregation of deposited copper species (UV-vis-DRS), surface acidity (NH<sub>3</sub>-TPD) and reducibility (H<sub>2</sub>-TPR). The samples of the Cu-ITQ-6 and Cu-ITQ-36 series were found to be significantly more active NH<sub>3</sub>-SCR catalysts compared to Cu-FER. The activity of these catalysts in low-temperature NH<sub>3</sub>-SCR was assigned to the significant contribution of highly dispersed copper species (monomeric cations and small oligomeric species) catalytically active in the oxidation of NO to NO<sub>2,</sub> which is necessary for fast-SCR. The zeolitic catalysts, with the higher framework alumina content, were more effective in high-temperature NH<sub>3</sub>-SCR due to their limited catalytic activity in the side reaction of ammonia oxidation.
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