Ceramic foam monoliths as catalyst carriers. 1. Adjustment and description of the morphology

Many properties of open-cell ceramic foam monoliths prepared by means of the sponge replication method can be controlled by adjusting the viscosity of the ceramic slip to the pore count of the templating polymer sponge. Catalyst carriers with tailored strut thicknesses, relative densities, and void fractions in the range of 0.77-0.95 can thus be produced. A structural model based on the dense packing of tetrakaidekahedra is useful for an approximate description of the morphology of the foams. With this model, it is possible to estimate the mean pore diameter, the mean thickness of the struts, and the minimum surface area from two macroscopic parameters that are easily accessible by simple experimental methods. A comparison between the calculated minimum surface area and the BET surface area can provide information about the roughness of the struts.