Patent ID: 6849181

Claim:
A diesel exhaust particulate filter comprising a plugged, wall-flow honeycomb filter body composed of porous ceramic material and comprising a plurality of parallel end-plugged cell channels traversing the body from a frontal inlet end to an outlet end thereof, wherein: the ceramic contains, expressed in terms of weight percent of the total body, of 60-90% iron-aluminum titanate solid solution having a stoichiometry of Al 2(1−x) Fe 2x TiO 5 , where x is 0-0.1, and 10-40% mullite (3Al 2 O 3 .2SiO 2 ), and consists essentially, expressed in terms of weigh percent on the oxide basis, of 3 to 15% SiO 2 , 55 to 65% Al 2 O 3 , 22 to 40% TiO 2 , and 0 to 10% Fe 2 O 3 ; and, the filter has a porosity of 35% to 55% by volume, a median pore size of 8 to 20 micrometers, a permeability of at least 0.30×10 −12 m 2 when fired to a temperature of between 1650° to 1700° C., and, an increment in a linear dimension of less than 1% after the filter has been exposed one hundred times to thermal cycling at a temperature of 200° to 1100° C. in a time of 7 minutes, and cooling from 1100° to 200° C. in a time of 7 minutes.