[01] Jihene Jemal, Department of Chemistry, Faculty of Sciences, Tunis, Tunisia. [02] Carolina Pettito, Institute Charles Gerhardt, National School of Chemistry, Montpellier, France. [03] Gérard Delahay, Institute Charles Gerhardt, National School of Chemistry, Montpellier, France. [04] Zouheir Ksibi, Department of Chemistry, Faculty of Sciences, Tunis, Tunisia. [05] Hassib Tounsi, Department of Materials Engineering, National School of Engineers, Sfax, Tunisia.

Copper loaded hydroxyapatite catalysts have been prepared in organic medium by reaction/evaporation and impregnation methods and have been tested in the selective catalytic reduction of NO by NH₃. The catalyst characterizations showed the presence of CuO and Cu₂O particles deposited on the surface of the carrier in different environments and sizes. Compared to the catalysts prepared by ion exchange and impregnation in aqueous medium method, the ones prepared in organic medium are less efficient in the selective catalytic reduction of NO by NH₃.

NH₃-SCR, NO, Cu(acac) ₂, Cu-HAp

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