Honeycomb structure comprising an outer cement skin and a cement therefor

摘要

A honeycomb catalyst support structure including a honeycomb body and an outer layer or skin formed of a cement is described. The cement includes an amorphous glass powder with a multimodal particle size distribution applied to an exterior surface of the honeycomb body. The multimodal particle size distribution is achieved through the use of a first glass powder having a first median particle size and at least a second glass powder having a second median particle size. In some embodiments, the first and second glass powders are the same amorphous glass consisting of fused silica. The cement may further include a fine-grained, sub-micron sized silica in the form of colloidal silica. The cement exhibits a coefficient of thermal expansion less than 15×10−7/° C., and preferably about 5×10−7/° C. after drying.

主权项

1. A honeycomb structure comprising:
a ceramic honeycomb body including a plurality of cells extending axially between first and second opposing end faces of the honeycomb body, the plurality of cells defined by intersecting porous walls; and a calcined cement layer comprising fused silica having a particle size distribution with a D50 in a range from 150 to 300 μm disposed over a periphery of the honeycomb body, wherein an average coefficient of thermal expansion of the calcined cement layer from a temperature of 600° C. on cooling to 23° C. is equal to or less than 15×10−7/° C.