Effects of surface chemical properties of activated coke on selective catalytic reduction of NO with NH3 over commercial coal-based activated coke

Abstract

Surface chemical properties of typical commercial coal-based activated cokes were characterized by X-ray photoelectron spectroscopy (XPS) and acid-base titration, and then the influence of surface chemical properties on catalytic performance of activated cokes of NO reduction with NH3 was investigated in a fixed-bed quartz micro reactor at 150 °C. The results indicate that the selective catalytic reduction (SCR) activity of activated cokes with the increase of its surface acidic sites and oxygen content, obviously, a correlation between catalytic activity and surface acidic sites content by titration has higher linearity than catalytic activity and surface oxygen content by XPS. While basic sites content by acid-base titration have not correlation with SCR activity. It has been proposed that surface basic sites content measured by titration may not be on adjacent of acidic surface oxides and then cannot form of NO2-like species, thus the reaction of reduction of NO with NH3 have been retarded. Keywords: Activated coke, SCR, Surface chemical properties, Catalytic reduction