A series of MnO 2 /carbon nanotubes (CNTs) catalysts were prepared to use for the selective catalytic reduction (SCR) of NO with NH 3 via liquid-phase redox method at ambient temperature. The resulting samples possessed an amorphous MnO 2 and, a higher SCR activity than that obtained by wet impregnation technique.
A series of MnO 2 /carbon nanofibres (CNFs) catalysts were prepared by a facile co-precipitation method for low-temperature selective catalytic reduction (SCR) of NO with NH 3. These catalysts were characterised by the techniques of specific surface area measurements (BET), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and H 2 temperature-programmed reduction (H 2-TPR). The XRD, FESEM and TEM results showed that the CNFs were surrounded by MnO 2 nanoflakes. Compared with the MnO x /CNFs catalyst prepared by the wet impregnation method, the MnO 2 / CNFs catalysts exhibited better low-temperature SCR activity at low temperature. The XPS results indicated that a higher concentration of Mn 4+ and more surface oxygen species exited on the surface for 8% MnO 2 /CNFs catalyst. The H 2-TPR profiles displayed that the 8% MnO 2 /CNFs catalyst presented stronger low-temperature reducibility than the MnO x /CNFs catalyst. Based on the abovementioned favourable properties, the 8% MnO 2 /CNFs catalyst has an excellent performance in the low-temperature SCR of NO with NH 3 .
Pristine multiwalled carbon nanotubes (MWCNTs) were modified by sodium dodecyl sulfate (SDS).Afterwards, a series of MnO 2 /MWCNTs were prepared via a redox method and used in selective catalytic reduction (SCR) of NO x at 80-180℃. Structural properties and catalytic performance were investigated by specific surface area measurements (BET), X-ray diffraction (XRD), filed emission scanning electron microscope (FESEM), transmission electron microscope (TEM), X-ray photoelectron spectroscope (XPS), and H 2 temperature-programmed reduction (H 2 -TPR). The characterization results indicate that the nanoflaky MnO 2 highly disperse on MWCNTs. The results show that the low-temperature SCR activities of MnO 2 /MWCNTs catalysts are 85%-100% at 140-180℃ at a weight hourly space velocity of 210 L/(g cat •h), higher than that of catalyst fabricated via the wet impregnation method.The 10% MnO 2 /MWCNTs catalyst displays first-rate SCR activity, which is attributed to its low crystallinity, high concentrations of Mn 4+ and oxygen absorbtion onto the catalyst surface, as well as excellent reducibility. Additionally, compared to the MnO x /MWCNTs catalyst, the 10% MnO 2 /MWCNTs catalyst exhibits higher resistance to H 2 O and SO 2 .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.