Ceramic diesel particulate filters - Status and trends

The introduction of diesel particle filters (DPF) in European passenger cars in 2000 was a real breakthrough from both, a scientific and a commercial point of view and has been boosting to a success story. Wall flow filters made of silicon carbide ceramics seem to be at advantage in cars because of their robustness. But aluminium-titanate, cordierite and mullite are of growing interest in future applications. Higher cell density, asymmetric cell design and catalysed filters have been developed and introduced in the market recently. Future regulations will force nearly each diesel motor to be equipped with sophisticated emission control systems as DeNOx and DPF (or both) in the near future. A more comprehensive overview was given elsewhere [1] 2005. This paper tries to give a short and updated overview about the required properties, known systems and materials and their prospects from the material scientific as well as from the commercial aspect.