Development of a novel design for diesel particulate filter

A novel design for diesel particulate emission filter based on wall structure of pore channels of honeycomb filter is proposed. Our anticipation in this new design is that, if whiskers are coated on walls of the pore channels of honeycomb filter, the trapping efficiency of honeycomb filter will be improved and also the pressure drop will be substantially reduced. In present study, cordierite whiskers were coated on cordierite based honeycomb support (diameter 13 cm, and height 14.5 cm, 600 cells/inch(2)) by in-situ method. Whisker coating was carried out on walls of the pore channels of cordierite support from aqueous slurry containing a mixture of kaolin, talc, alumina and silica. Coating was performed by wash coat method. Firing was carried out at 1350degreesC for 4 h under flowing air atmosphere. XRD measurements revealed us complete formation of cordierite phase. SEM analysis on the coating showed the formation of three-dimensional network of cordierite whiskers on cordierite support. In order to evaluate the particulates trapping efficiency of the newly developed honeycomb filter, smoke test was carried out with a 2L diesel engine for the both un-coated and coated cordierite honeycomb samples and the results were discussed with respect to their microstructures.