Gasoline Engine Twc Three Way Catalyst Platinum Palladium Rhodium Wall Flow Configuration

GPF (Gasoline Particulate Filter)Euro 6 PN Filtration for After-treatment System

GPF (Gasoline Particulate Filter)

• GPF (Gasoline Particulate Filter) is installed at the outlet of gasoline vehicle engine. It can capture particulate emissions before they enter the atmosphere. Generally, the one with a three-way catalytic coating is called cGPF.
• GPF is currently in a wall-flow configuration. After the air enters the pore channel, it passes through the carrier wall to the adjacent pore channel and flows out. During the process of passing through the wall, the particles in the air flow are intercepted by the GPF to achieve the particle trapping effect.

With upcoming legislations in Europe and China requiring compliance with a particle number (PN) limit of 6*10¹¹/km, particulate filters will be applied for gasoline engines. It is favorable to combine the catalytic activity for the conversion of gaseous pollutants with the reduction of particulates in one step. This can be achieved with catalysed gasoline particlulate filters (cGPF).

The working principle of the cGPF is comparable to the well-established catalyzed diesel particulate filters (cDPF). Particulate matter is removed from the exhaust by physical filtration using a honeycomb structure similar to an emissions catalyst substrate but with the channels blocked at alternate ends. The exhaust gas is thus forced to flow through the porous walls between the channels and the particulate matter is deposited on and in the walls. The catalytic coating provides TWC activity and converts CO, HC and NO_x simultaneously.

To meet Euro 6 / China-VI stage light-duty vehicles PN emission requirements, WFEC developed WFG series cGPF catalysts. WFEC cGPF catalysts can achieve excellent PN filtration rate through optimized washcoat design and distribution. By improve of washcoat material and coating process, the backpressure of cGPF catalyst is largely decreased, thus the negative influence on engine fuel economy by cGPF is obvious lowered. And the active catalytic washcoat on cGPF can deeply purify gas pollutant (such as THC, CO and NO_x) and fulfill Euro 6 / China-VI aging requirements. cGPF can install in CC (Close-coupled) or UF (Under-floor) position, applying together with TWC. The vehicle emission of PN and gas pollutant is able to completely satisfy Euro 6 / China-VI regulations after employing WFEC TWC+cGPF aftertreatment system.