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Stricter regulatory standards are continuously adopted worldwide to control heavy duty emissions, and at the same time, fuel economy requirements have significantly lowered exhaust temperatures. The net result is a significant increase in Precious Group Metal (PGM) usage with current Diesel Oxidation Catalyst (DOC) technology. Therefore, the design and development of advanced DOC with ultra-low PGM to achieve highly beneficial emission performance improvement is necessary. The advanced DOC is synergized PGM (SPGM) with Mixed Metal Oxide (MMO). The presence of MMO in SPGM is responsible for NO oxidation to NO2 which is critical for the passive regeneration of the downstream filter and SCR function. This paper outlines the development of MMO for application in modern DOCs and addresses some specific challenges underlying this application. Lab and flow reactor data demonstrates MMO by itself owns great oxidation properties with high surface area available for NO oxidation reaction.

In the context of evolving market conditions, the three-way catalyst (TWC) design is entering an exciting new phase. It remains the main emission control strategy for gasoline powered vehicles in the broad context of evolving engine technology; the move to more real-world, transient testing and much tighter tailpipe emissions regulations. The specific context here is the launch of BSVI regulations for gasoline passenger cars in India. The key approach described here is to achieve highly beneficial emission performance based on low PGM levels with the emphasis on new materials technology to significantly alter the functional balance between PGM and “promoters”. We will focus on the design of materials with the spinel structure and have developed catalyst products that synergize low levels of PGM (so-called SPGM) leveraging the key properties of the advanced spinel oxides. Microstructure studies on the spinel oxide with newly developed composition confirm the aging stability [1,2].

Stricter regulatory standards are continuously adopted worldwide to control heavy duty emissions, and at the same time, fuel economy requirements have significantly lowered exhaust temperatures. The net result is a significant increase in Precious Group Metal (PGM) usage with current Diesel Oxidation Catalyst (DOC) technology. Therefore, the design and development of synergized precious metal (SPGM) in which ultra-low PGM is synergized with mixed metal oxide (MMO) to achieve highly beneficial emission performance improvement, is necessary. The presence of MMO in SPGM is responsible for NO oxidation to NO2 which is critical for the passive regeneration of the downstream filter and SCR function. This paper presents an initial study outlining the development of MMOs for application in modern DOCs and addresses some specific challenges underlying this application. Lab and flow reactor data in this study demonstrated SPGM DOCs thermal resistance and sulfur poisoning resistance.

In the context of evolving market conditions, the three-way catalyst (TWC) design is entering an exciting new phase. It remains the main emission control strategy for gasoline powered vehicles; in the meantime a rapid period of evolving engine developments, the constrained tailpipe regulations and the material supply issues present a unique challenge to the catalyst developers. A key approach here is to achieve highly beneficial emission performance based on the ultra-low PGM levels. In this regard, we mainly focus on the materials design and have developed the advanced spinel oxides for zero precious metals (ZPGM) and synergized precious metals (SPGM) TWCs. These advanced spinel materials showed improved thermal stability compared to that of PGM based standard materials. Fundamental studies on the microstructure of spinel oxide with newly developed composition confirm the aging stability.

In the context of evolving market conditions the Three-Way Catalyst (TWC) is entering an exciting new phase. It remains the main emission control strategy for gasoline powered vehicles but a period of rapidly evolving engine development, tighter tailpipe regulations and material supply issues present a unique challenge to catalyst developers. This paper presents an initial study outlining the development of spinel mixed metal oxides for application in modern TWC and addresses some specific challenges underlying this application. Lab and flow reactor data in the study showed how the spinel structure has significant potential in various aspects of the TWC with the necessary improvement in thermal stability. Some initial engine data show three-way performance at or near stoichiometric in a PGM and rare earth free spinel coating and a synergy effect when combined with PGM.

Non-PGM catalyst containing base metal mixed oxide (BMMO) supported on rare earth mixed oxide (REMO) had been evaluated by various methods for soot-oxidation activity. Thermo-gravimetric/Differential Thermal Analysis (TG/DTA) experiments and synthetic gas bench activity tests showed that the catalyst was able to oxidize soot at temperatures significantly lower than soot combustion temperature leading to a conclusion that soot was oxidized via direct reaction with active species of the catalyst surface. It had been shown that low-temperature soot oxidation occurred with and without NO present in the reaction gas. Evaluation on engine benches of the BMMO catalyst coated on diesel particulate filters (DPF) confirmed low-temperature soot oxidation in exhaust gas with low NO₂ concentration and a possibility of cost-efficient diesel exhaust aftertreatment system without increasing tailpipe NO₂ content.

Catalytic Solutions, Inc. has developed a breakthrough catalyst technology utilizing new mixed metal oxides in conjunction with Platinum Group Metals. Stable synergies are designed into the catalyst washcoat that enable high three-way performance durability to be achieved at low precious metal usage. Several vehicle test cases will be reported showing how this low-PGM technology meets LEV-II and ULEV-II performance levels. Catalyst technology developments discussed in the vehicle setting will be referenced with flow reactor studies that simulate critical FTP performance features. Results of characterization studies on fresh and aged coatings will be described, and discussed in the context of vehicle aging factors.

A breakthrough catalyst technology utilizing new mixed metal oxides in conjunction with Platinum Group Metals has been developed. Stable synergies are designed into the catalyst washcoat that enable high performance and durability to be achieved at low Platinum Group Metal usage. Extensive vehicle data is reported on catalysts aged using a variety of high-temperature accelerated aging cycles. Vehicle performance at the LEV, ULEV and LEV-II levels is discussed in the context of unique calibration-catalyst interactions. Conclusions concerning further areas of improvement and future applications are also reviewed.