CuAPSO-34 catalysts for N2O decomposition in the presence of H2O. A study of zeolitic structure stability in comparison to Cu-SAPO-34 and Cu-ZSM-5

The structural stability at high temperatures of both Cu-exchanged SAPO-34 and CuAPSO-34 with isomorphously substituted copper ions has been investigated. SAPO-34 undergoes an extensive crystallinity loss upon copper ion exchange. The CuAPSO-34 framework showed good hydrothermal stability, as reflected in its surface area and X-ray diffraction pattern after ageing treatments. This catalyst exhibited good activity in N2O decomposition even when the reaction was run in the presence of H2O or after ageing treatment under H2O vapor at 600degreesC for 80 h which, conversely, led to a drastic loss of activity of Cu-ZSM-5.