ENVIRONMENTAL LOAD OF sulphur FROM STORAGE CATALYSTS

Abstract

Under the development of quality standards for fuels was the theoretical basis of storage-reduction catalyse with sulphur also examined. Lowering the NO_x emission of motor vehicles powered by an Otto-motor with direct fuel injection can be done in the most effective way by the use of a NO_x storage catalyst. But sulphur-regeneration shows a strongly negative impact on NO_x conversion. In contrast to SCR catalysts sulphur content in exhaust gas can cause here strong detractions in normal operation of the catalysts. An on-board analysator has been developed and built to recognize SO₂, H₂S and CO₂ concentration of the exhaust gas simultaneously both at the test bench and while drive. SO₂ and H₂S are measured by electro-chemical cells while CO₂ concentration is detected optically based on infrared light adsorption. This device gives reliable data about the emission in one second timing during the regeneration phase of the storage catalyst. This system makes NO_x storage more manageable, secure and optimised with regard to the increasing notability of the `in-use compliance´.