Chemical Engineering Journal, Vol.116, No.1, 25-37, 2006
Catalytic oxidation of NO by activated carbon fiber (ACF)
Catalytic oxidation of NO was carried out on activated carbon fibers (ACFs) based on various precursors in a packed bed tubular reactor under varying reaction temperatures (30-80 degrees C) and inlet NO (100-400 ppm) and 02 (5-100%) concentrations. Maximum conversion of NO was obtained at the reaction temperature of 30 degrees C and with increasing O-2 concentrations. The performance of the phenolic resin-based ACF was found to be superior to that of the viscose rayon and pitch-based ACFs. The phenolic resin-based ACF samples were also synthesized in the laboratory by carrying out carbonization and activation of the corresponding raw carbonaceous fibers under varying activation temperatures (800-1000 degrees C), activation agents (CO2 and steam) and activation time (30-90 min). The results of the surface characterization of ACF in relation to their oxidation characteristics revealed that the oxidation of NO was favored on the ACF samples having relatively lesser extent of the CO evolving surface O-2 functional groups. A surface kinetic mechanism for the oxidation of NO was proposed and incorporated in a transport model developed to explain the experimental breakthrough data. (c) 2005 Elsevier B.V. All rights reserved.