Patent ID: 7842371

Claim:
A porous ceramic article, comprising: a honeycomb ceramic structure defining a plurality of cell channels bounded by porous cell channel walls having a porosity % P that extend longitudinally from an upstream inlet end to a downstream outlet end, wherein the plurality of cell channels are present in a cell channel density of “X” cells per square inch; and a catalyst containing washcoat applied to the porous cell channel walls in a washcoat loading amount “WC” of at least 40 g/l such that the washcoat loading amount “WC” satisfies the relationships of: X 1 =5.95·10 −3 ×WC 2 +2.44 ×WC− 36.8, and X 2 =−1.46·10 −2 ×WC 2 +3.89 ×WC+ 255, wherein X 1 ≦X≦X 2 ; wherein the porous cell channel walls have a wall thickness of “Y” that satisfies the relationship Y 1 ≦Y≦Y 2 ; wherein Y 1 =( A·X 2 )+( B·X )+ C, wherein Y 2 =( D·X 2 )+( E·X )+ F; wherein: A = 1.10 · 10 - 12 × WC 4 - 4.25 · 10 - 10 × WC 3 + 5.92 · 10 - 8 × WC 2 - 3.23 · 10 - 6 × WC + 1.38 · 10 - 4 ; B = - 3.95 · 10 - 10 × WC 4 + 1.4 · 10 - 7 × WC 3 - 1.89 · 10 - 5 × WC 2 + 6.32 · 10 - 4 × WC - 5.60 · 10 - 2 ; C = 4.18 · 10 - 6 × WC 3 - 6.11 · 10 - 4 × WC 2 + 2.08 · 10 - 1 × WC + 3.74 ; D = - 1.04 · 10 - 12 × WC 4 + 3.94 · 10 - 10 × WC 3 - 5.33 · 10 - 8 × WC 2 + 2.83 · 10 - 6 × WC - 1.31 · 10 - 4 ; E = 3.97 · 10 - 10 × WC 4 - 1.41 · 10 - 7 × WC 3 + 1.65 · 10 - 5 × WC 2 - 4.63 · 10 - 4 × WC + 1.68 · 10 - 2 ; and F = - 4.65 · 10 - 8 × WC 4 + 1.65 · 10 - 5 × WC 3 - 1.75 · 10 - 3 × WC 2 + 8.98 · 10 - 2 × WC + 8.56 ; and wherein % P is in the range of from 40% to 80%.