MEASUREMENT OF THE EFFECTIVE DIFFUSION-COEFFICIENT OF NITROGEN MONOXIDE THROUGH POROUS MONOLITH-TYPE CERAMIC CATALYSTS

This Research Note describes a straightforward experimental technique to measure the effective diffusion coefficient of nitrogen monoxide through the porous walls of a monolith-type ceramic catalyst. The method takes explicit advantage of the geometric shape of a monolith-type catalyst to measure the steady-state diffusion flux of nitrogen monoxide through the porous catalyst. It is found that the tortuosity factor of the commercial titania-supported catalysts used in this study and employed for the selective catalytic reduction of NO by NH3 ranges from 2.0 to 2.3.