Development of Membrane filter Made of Alumina and Silver-Palladium Particles for High-Filtration Efficiency, Low-Pressure Drop and Low-Soot Oxidation Temperature

Abstract

A membrane filter was coated on conventional filter made of SiC. The first and second layers consisted of aluminaparticles with diameter of 0.5 and 1.5 micrometer, respectively; because small particles have higher filtration efficiency to prevent soot penetration into the membrane layer while large particles with a higher permeability can achieve lower pressure drop. Nanoscale silverpalladium particles were dispersedly deposited on the surface of the alumina particles layer as a top layer. The novel membrane filter demonstrated lower pressure drop while keeping high trapping efficiency during the soot trapping and presented lower soot oxidation temperature compared to the conventional filter.

Numerical Design of Granular Support for Three-Way Catalyzed Solid- and Porous-Particles Membrane Filters

“…Introduction of a membrane has been shown to prevent soot deposition inside the GPF pores at the initial state because the GPF pores were already filled by the membrane. Thus, utilizing a higher membrane permeability compared to soot yielded a lower pressure in long-term soot trapping compared to a conventional particulate filter [ 6 , 7 ], as shown in Figure 2 . Moreover, the membrane could provide almost complete filtration efficiency from the beginning owing to pre-loaded membrane particles in the particulate filter pores, overcoming this limitation of the conventional particulate filter [ 4 ].…”

“…Poly(methyl methacrylate) (PMMA) was used as a template [ 9 ]. Porous-TWC particles were fabricated on a particulate filter using the methodology of previous studies [ 6 , 11 ]. The porous structure can be classified according to its pore size.…”

Modeling of CO Oxidation by Diffusion of Oxygen Atoms in Ceria-Zirconia Particulates in a Three-Way Catalyst Particle Membrane Filter

“…Recently, particle membrane filters have been manufactured by the authors using various catalyst components with the aim of improving soot oxidation kinetics and mitigating exhaust gas pollutants [12][13][14]. In contrast to wash-coated catalyzed particulate filters as mentioned above, catalyst particles were percolated as a membrane on the surface of a GPF substrate, which results in almost 100% filtration efficiency from the beginning of soot trapping and a low pressure-drop filter compared with the conventional filters [15].…”