A porous ceramic substrate is disclosed that is fabricated from biosoluble
ceramic fibers. Porosity and permeability of the substrate is provided by
intertangled biosoluble fibers, that can be formed into a honeycomb form
substrate through an extrusion process. The fibrous structure is formed
from mixing biosoluble fibers with additives that include a bonding
agent, and a fluid to provide an extrudable mixture. The structure is
sintered at a temperature that exceeds the glass formation temperature of
the bonding agent, but less than the maximum operational limits of the
biosoluble fiber, to form a structure that has sufficient strength and
porosity to provide for filtration and/or as a catalytic host.