Low temperature SCR of NO with NH 3 over carbon nanotubes supported vanadium oxides

Abstract

A novel multiwalled carbon nanotube (CNTs) supported vanadium catalyst was prepared. The structure of catalyst prepared was characterized by TEM, BET, FTIR, XRD and temperature-programmed desorption (TPD) methods. The results indicated that vanadium particles were highly dispersed on the wall of carbon nanotubes. The V 2O 5/CNT catalysts showed good activities in the SCR of NO with a temperature range of 373–523 K. The Lewis acid sites on the surface of V 2O 5/CNT are the active sites for the selective catalytic reduction (SCR) of NO with NH 3 at low temperatures. It was suggested that the reaction path might involve the adsorbed NH 3 species reacted with NO from gaseous phase and as well as the adsorbed NO 2 species. The diameter of CNTs showed positive effect on the activities of the catalysts. Under the reaction conditions of 463 K, 0.1 Mpa, NH 3/NO = 1, GHSV = 35,000 h −1, and V 2O 5 loading of 2.35 wt%, the outer diameter of CNTs of 60–100 nm, the NO conversion was 92%.