New Approach for Pore Structure and Filtration Efficiency Characterization

Pore structure in Diesel Particulate Filter (DPF) materials is usually described in terms of the porosity and pore size, typically measured by mercury porosimetry. Filtration efficiency is in general lower for materials with higher porosity and pore size but this is not always supported by experimental correlations of filtration efficiency and mercury porosimetry data. In the present paper a new approach for the characterization of DPF pore structure is presented based on the combination of mercury porosimetry data and microscopic image analysis. The new approach shows that a monotonic relation can be obtained for the correlation of the filtration efficiency to a certain composite microstructural descriptor. The new characterization approach provides a better understanding of the microstructural factors that are affecting the filtration efficiency of DPFs.