High filtration efficiency particulate filters having bimodal pore size distribution made from beads with open porosity

A method of manufacturing a particulate filter, comprising:

• mixing together a batch mixture comprising a plurality of porous ceramic spheroidal beads each comprising a porous ceramic material,
• shaping the batch mixture into a green honeycomb body;
• firing the green honeycomb body into a ceramic honeycomb body by sintering together the plurality of porous ceramic spheroidal beads into an interconnected network of the plurality of porous ceramic spheroidal beads, wherein the ceramic honeycomb body comprises a plurality of intersecting walls that define channels extending axially between opposite end faces of the ceramic honeycomb body, wherein a microstructure of the plurality of intersecting walls comprises the interconnected network of the plurality of porous ceramic spheroidal beads;
• and
• alternatingly plugging at least some of the channels at the opposite end faces of the ceramic honeycomb body to form the particulate filter;
• wherein the microstructure has a total porosity defined as the sum of an open intrabead porosity of the plurality of porous ceramic spheroidal beads and an interbead porosity defined by interstices between the plurality of porous ceramic spheroidal beads in the interconnected network;
• and
• wherein the microstructure has a bimodal pore size distribution in which an intrabead median pore size of the plurality of porous ceramic spheroidal beads is from 1.5 μm to 4 μm and an interbead median pore size of the interstices between the plurality of porous ceramic spheroidal beads is from 6 μm to 20 μm.