A Novel, Smaller Honeycomb for Significant PGM Saving

Mansour  Masoudi, Emissol LLC

M. Masoudi¹, E. Tegeler¹, T. Toops², V. Prikhodko², J. Pihl² , V. Balakotaiah³

¹ Emissol LLC, Mill Creek, Washington
² Oak Ridge National Laboratory, Oak Ridge, Tennessee
³ University of Houston, Houston, Texas

This is an update on developing a novel, smaller emission control honeycomb requiring substantially lower PGM loading. The honeycomb utilizes helical channels, instead of the commonplace straight channels, developing a strong vortex flow inducing convective species transport to the washcoat instead of the slow, diffusive transport commonly seen in straight channels. Last year, we reported on testing model honeycombs using single species (CO) concentration in both stoichiometric (gasoline) and lean (Diesel) exhaust conditions; it was shown that, owing to its strong, convective mass transfer, the new helical channel honeycomb utilizing 30% or more PGM reduction, provides same or better performance that the standard one.

The novel honeycomb was further evaluated using multi-species (CO, NO, light and heavy hydrocarbons) in the LTAT S-GDI protocol (US-CAR). Various volume-PGM reduction combinations were tried. Results indicate that, while helical channel honeycombs are smaller (downsized) than standard honeycombs and require markedly less PGM, they are nevertheless more efficient, light off earlier (have improved T50 and T90 temperatures) and have potentials to reduce HC slip.  In all, performance of the novel honeycomb requiring markedly less PGM loading is on par with or exceeds that of mainstream (standard) honeycombs.

Efforts are underway to develop a low-cost manufacturing technique.

NOTE: Funding for this undertaking was provided by the US Department of Energy, under the guidance of Mr. Ken Howden.