Evaluation of Catalytic Soot Oxidation Activity

Method for Evaluation of Catalytic Soot Oxidation Activity 

Under practical scale and reaction conditions using DPF test pieces loaded with catalysts and engine exhaust gases, the catalytic performance is often evaluated by the balance point temperature (BPT Fig. 2.4b), which is determined from the changes in pressure drop (Ap) through the DPF with time at different temperatures. At low temperatures, Ap increases with time as PM accumulates on the DPF. As the temperature is raised, the PM oxidation rate increases and finally exceeds the PM accumulation rate at a certain point, which results in a decrease in pressure drop across the DPF with time. The BPT is defined as the temperature at which the rate of change of Ap is equal to zero. 

Junko Uchisawa, Akira Obuchi and Tetsuya Nanba 

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