Catalytic Oxidation of NO over CNF/ACF-Supported CeO2 and Cu Nanoparticles at Room Temperature

The present study describes the development of carbon micro- and nanofibers (CNFs) in situ dispersed with ceria (CeO2) and Cu metal nanoparticles (NPs) for the oxidative removal of NO at room temperature. CNFs/activated carbon fibers (ACFs) were prepared by growing CNFs on an ACF substrate using chemical vapor deposition at 450 °C. The Cu NPs played dual roles: (1) catalyzing the growth of the CNFs and (2) catalytically oxidizing NO to NO2. The synergistic interaction between the Cu NPs and CeO2 enhanced the oxidation rate. The maximum NO conversion using the CeO2–Cu–CNFs/ACFs developed in this study was ∼80% for a 500 ppm NO concentration at room temperature (∼30 °C). A mathematical model was developed to explain the proposed mechanism for NO oxidation, incorporating the kinetic rate and mass-transfer effects in the tubular reactor. The CNF/ACF-supported CeO2 and Cu bimetal catalyst prepared in this study represents a promising candidate for abating NO emissions by oxidation at room temperature.