论文信息 - Construction of the tortuosity factor from porosimetry

Construction of the tortuosity factor from porosimetry

The tortuosity factor for volume diffusion in porous solids, τ, is constructed mathematically from properties of their connected porosity based on Hg porosimetry and related measurements. Noncylindrical diffusion paths are identified and incorporated in the construction. The resulting equation, τ = x · (0.92y)1+e, for the first time makes possible the computation of τ without recourse to diffusion measurement. The term x is a function of pore volume; y is derived from porosimetry and surface area data; and e is obtained from ordinary D(ϱ) vs ϱ data where p is pore radius. The computed τ agrees with diffusion-determined values for many catalysts and other oxidic materials.

S. C. Carniglia

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