Next Generations of Gasoline Particulate Filters for Catalyzed Applications

Gasoline particulate filters (GPF) have become a standard aftertreatment component in Europe, China, and since recently, India, where particulate emissions are based on a particle number (PN) standard. The anticipated evolution of regulations in these regions towards future EU7, CN7, and BS7 standards further enhances the needs with respect to the filtration capabilities of the GPFs used. Emission performance has to be met over a broader range in particle size, counting particles down to 10nm, and over a broader range of boundary conditions. The requirements with respect to pressure drop, aiming for as low as possible, and durability remain similar or are also enhanced further.To address these future needs new filter technologies have been developed. New technologies for uncatalyzed GPF applications have been introduced in our previous publications. In this contribution we will describe novel Generation 2 and 3 technologies of Corning’s high porosity Corning® DuraTrap® GC HP filters for applications in which the GPF is capable of being coated with a catalyst. The new technologies are based on improved microstructure and Corning’s proprietary Accelerated Purification Technology (APT) to enable a hierarchical pore design, respectively. In the paper we will describe the generic product concept of these new technologies and present test data obtained in the laboratory as well as vehicle and engine bench testing. The test data are based on well-defined laboratory test procedures as well as procedures representing real world driving conditions. To address the global character of GPFs, test data from European as well as Chinese vehicle applications and test programs will be discussed. The test data will demonstrate that with the new technologies very high filtration efficiencies can be obtained also for catalyzed GPFs, without having to tolerate an excessive pressure drop.