Cu/zeolite SCR catalyst for NOx reduction in exhaust gases and manufacture method thereof

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The present invention describes a method of preparation and/or modification of Cu/zeolite catalysts designed for the SCR of nitrogen oxides with ammonia, including commercial catalysts. The method is comprising a removal of extra-lattice (extra-framework) aluminum species together with copper ions using citrate solution and a following re-insertion of copper or insertion of Cu/M ions, where M = Mg, Ca, Sr, La, Pr, B, Zr or Mg-Fe or Mg-Ce, using ion-exchange and/ or impregnation. The modified catalyst has improved and high NOx reduction properties at temperatures 170-600°C and excellent hydrothermal stability up to 900°C.