abstract |
The invention provides methods for a one-pot synthesis of molecular sieves of the CHA-type. The method uses molecular and non-molecular sieves as sources of silicon and aluminum. A first OSDA is selected from tetraethylenepentamine (TEPA) and triethy-lenepentamine (TETA). The synthesis mixture comprises a first metal selected from copper, iron and zinc. Optionally, the synthesis mixture may furthermore comprise a second OSDA and/or a second metal selected from manganese, cesium, magnesium, calcium, strontium, barium, yttrium, titanium, zirconium, niobium, iron, zinc, silver, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium and mixtures thereof. The molecular sieves of the CHA-type obtainable by the method can be used as SCR-catalytically active substances for the removal of nitrogen oxides from exhaust gases of combustion engines. |