Catalyzed Gasoline Particulate Filters: Integrated Solutions for Stringent Emission Control

摘要

Upcoming Euro 6 regulation will enforce beside the well-known limits for hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NO_x) also tighter control of particulate matter emissions from gasoline-engine powered vehicles. The European Commission has decided to implement new standards for the maximum number of particulates in two phases. Phase 1 will start with an initial limit of 6×10~(12)/km in 2014 followed by phase 2 (Euro 6c) with a more stringent standard of 6×10~(11)/km in 2017. In addition, Real-Driving Emissions (RDE) need to be considered from 2017 onwards. Three general approaches are currently followed to meet these challenging particulate legislation limits: 1. Changes to engine hardware and engine control strategies; 2. Addition of a non-catalyzed filter to the exhaust system; 3. Use of a catalyzed Gasoline Particulate Filter (c-GPF). The potentials and the limits of these concepts will be addressed. Introduction of gasoline particulate filter to TWC emission systems is regarded as the most sustainable solution to fulfill Euro 6c limits, RDE requirements and long-term durability. Approach 2 suffers from a drastically higher backpressure and higher system cost, while the integration of TWC functionality on a filter in form of a catalyzed Gasoline Particulate Filter (c-GPF) allows smart solutions to reduce backpressure and system cost. We will present latest results for c-GPF regarding filtration efficiency, back pressure, conversion performance and durability and discuss system solutions in combination with a TWC.