Preparation and characterisation of perovskite and noble metal promoted oxide based catalysts

Sammanfattning: This work concerns efforts to improve or replace noble-metal based catalysts used for car exhaust purification.Various oxide based catalysts have been prepared by impregnating washcoats such as (-Al2O3 and SiO2 with appropriate metal ions, and assemblies calcinated at elevated temperatures have been tested for catalytic activity in the oxidation of CO and C3H6 and reduction of NO. SEM-EDS, ATEM-EDS and XRD have been used for phase analysis and for studies of the morphology of catalysts prepared in situ. The perovskite compounds La1-xSrxMe1-2yCuyRuyO3 with Me = Al and Ga have been prepared, in situ and ex situ [SGIW1]respectively, and tested for catalytic activity. Changes in cell parameters and catalytic activity of in-situ LaAl1-xCuxO3 when exposed alternatingly to oxidising and reducing car exhaust atmospheres have been studied. The catalytic activity of various transition metal oxides with and without addition of Pt/Rh or Pd have also been tested.