Direct measurements of gas diffusivity in a washcoat layer under steady state conditions at ambient temperature

作者：Kato Satoru^*; Ozeki Hironobu; Yamada Hiroshi; Tagawa Tomohiko; Takahashi Naoki; Shinjoh Hirofumi

来源：Journal of Industrial and Engineering Chemistry, 2013, 19(3): 835-840.

DOI：10.1016/j.jiec.2012.10.028

• Catalyst
• Diffusion
• Porous material
• Pore size distribution
• Washcoat layer

A method for directly measuring gas diffusivity in a washcoat layer was established by preparing a simulated washcoat layer and modifying a Wicke-Kallenbach type counter-current diffusion cell. Three pairs of gases, N-2-Ar, CO2-Ar and C3H8-Ar, were used in the measurements. It was found to be possible to evaluate the pore-transport parameters of the washcoat layer based on the mean transport pore model and the modified Stefan-Maxwell equation. Analysis of the gas diffusion mechanism in the washcoat layer showed that bulk and Knudsen diffusion took place simultaneously, and the percentage value of the contribution by Knudsen transport to net diffusion transport was evaluated.

• 出版日期2013-5-25