Model Studies of Sulphur Deactivation of Nox Storage Catalysts

Model NO_x storage catalysts were used to study the sulphur deactivation of these systems using reactor studies, FTIR and XPS. It is found that the deactivation rate shows a linear dependence on the SO₂ concentration and that bulk sulphates are easily formed. Experiments with SO₂ present either during lean or during rich conditions show a more rapid deactivation in the latter case.