Abstract: The current invention refers to the LNT and the SCR catalysts designed for combined LNT-SCR applications. LNT catalysts are based on proton-conducting oxides of fluorite structure, namely Ca (Sr)—La—Ce (Zr, Pr) mixed oxides in which up to 40 mol-% of lanthanum is replaced by calcium and/or strontium, and up to 66 mol-% of cerium is replaced by zirconium and/or praseodymium, further combined with Pt—Pd or Pt—Pd—Rh precious metal components. SCR catalysts are Cu/zeolite modified by citrate treatment or Cu—Ce, Mn—Ce or Co—Ce/modified zeolite.

Abstract: Systems and methods for estimating an efficiency of a catalyst placed in an exhaust path of a combustion engine are disclosed. In one example approach, a method comprises: ageing the catalyst consecutively at different temperatures for definite time periods; measuring the catalyst conversion efficiency after each ageing step; calculating the ageing factor for each step of the ageing procedure and the accumulative value of the ageing factors for all steps of the ageing procedure; estimating catalyst efficiency correlation factors related to the measured catalyst conversion efficiency for each temperature point and for all ageing conditions; determining a correlation between the catalyst efficiency correlation factors and the accumulative value of the ageing factors; and calculating the conversion efficiency of the aged catalyst based on a predetermined correlation between the accumulative ageing factor and the catalyst efficiency correlation factor.

Abstract: Systems and methods for estimating an efficiency of a catalyst placed in an exhaust path of a combustion engine are disclosed. In one example approach, a method comprises: ageing the catalyst consecutively at different temperatures for definite time periods; measuring the catalyst conversion efficiency after each ageing step; calculating the ageing factor for each step of the ageing procedure and the accumulative value of the ageing factors for all steps of the ageing procedure; estimating catalyst efficiency correlation factors related to the measured catalyst conversion efficiency for each temperature point and for all ageing conditions; determining a correlation between the catalyst efficiency correlation factors and the accumulative value of the ageing factors; and calculating the conversion efficiency of the aged catalyst based on a predetermined correlation between the accumulative ageing factor and the catalyst efficiency correlation factor.

Abstract: The current invention refers to the LNT and the SCR catalysts designed for combined LNT-SCR applications. LNT catalysts are based on proton-conducting oxides of fluorite structure, namely Ca (Sr)—La—Ce (Zr, Pr) mixed oxides in which up to 40 mol-% of lanthanum is replaced by calcium and/ or strontium, and up to 66 mol-% of cerium is replaced by zirconium and/or praseodymium, further combined with Pt—Pd or Pt—Pd—Rh precious metal components. SCR catalysts are Cu/zeolite modified by citrate treatment or Cu—Ce, Mn—Ce or Co—Ce/modified zeolite.