Particulate Matter Oxidation over Ash-Deposited Catalyzed Diesel Particulate Filters

Abstract

Oxidation behavior of particulate matter (PM) in catalyzed diesel particulate filters (CDPFs) was investigated in the presence of ash through small-scale catalytic performance evaluation and visualization measurement. In the absence of ash, a CeO 2 -Ag CDPF reduces the PM oxidation temperature by approximately 100°C when compared with a CDPF with a Pt/Al 2 O 3 catalyst or a bare diesel particulate filter. The catalytic performance of the CeO 2 -Ag CDPF decreases in the presence of ash. However, this decrease is observed until the ash reaches 40 g/L in weight or 100 lm in thickness. An electron spin resonance analysis suggests that this remote PM oxidation is caused by the migration of superoxide species generated by the CeO 2 -Ag catalyst.

Soot oxidation in low-O2 and O2-free environments by lanthanum-based perovskites: structural changes and the effect of Ag doping

“…The enhancement of catalyzed, O 2 -mediated, soot oxidation is especially important over the cGPF, since unlike in the diesel cDPF, NO 2 is not available for low temperature passive regeneration. [22][23][24][25] In this manuscript La based perovskites, namely LaFeO 3 (low-OSC), LaMnO 3 (medium-OSC), and La 2 CuO 4 (high-OSC) and their Ag-doped analogues, are evaluated for soot oxidation by a reactivity test under cyclic oxidative/reductive conditions which enabled us to approximate catalytic changes that could take place under cGPF conditions. Ni, Co and Cr based La perovskites are not considered due to their toxicity and carcinogenic concerns, and for Co unfavorable O release dynamics were found in previous investigations.…”

“…The enhancement of catalyzed, O 2 -mediated, soot oxidation is especially important over the cGPF, since unlike in the diesel cDPF, NO 2 is not available for low temperature passive regeneration. 22–25…”

Review on Post-Treatment Emission Control Technique by Application of Diesel Oxidation Catalysis and Diesel Particulate Filtration

“…The results showed that ceria based catalysts are capable of accelerating soot combustion under real conditions. Cerium oxide (CeO2) based catalytic DPF oxidizes the particulate matter on ash layer up to thickness of about 100 µm whereas Platinum/Alumina based DPF promotes oxidation of PM up to ash layer thickness of 50µm only [45].…”

Decoding the Reactivity Enhancement of Ln2Ce2O7 Compounds (Ln = Yb, Y, Tb, and Gd) for Soot Combustion: The Remarkable Contribution of Variable Valence A-Sites

“…Diesel engines play an increasingly important role in the vehicle markets due to their high fuel efficiency and strong power. Nevertheless, the harmful impacts of emitted soot particles on the environment and human health have also become a major public concern, which cannot be neglected. , A catalyzed diesel particulate filter (cDPF) is regarded as one of the most perspective technologies to eliminate soot particle pollution . The catalysts coated on the DPF filter are crucial to promote soot oxidation activity and reduce the back pressure of the filter, thus maintaining good efficiency and desirable life-span.…”