NO removal by activated carbon-supported copper catalysts prepared by impregnation, polyol, and microwave heated polyol processes

The effect of HNO3 pretreatment of activated carbon (AC)-supported copper catalysts for NO removal with NH3 was studied. In addition, the effects of various preparation methods for Cu/AC catalysts, namely, impregnation (IM), polyol process (P), and microwave heated polyol process (MP), on the activity of NO removal with NH3 were compared. HNO3 pretreatment increased the number of carboxyl sites and promoted good dispersion of active sites. In addition, the chemical states of active phases were found to be affected when the catalysts were prepared by the microwave heated polyol process. More Cu2O particles were observed on the Cu/AC-N-MP catalyst than on the Cu/AC-N-P catalyst. The experimental results indicated that HNO3 pretreatment of the AC support led to increased catalytic activity for NO removal with NH3. The catalytic activity of the Cu/AC catalysts for NO removal at 200 °C decreased in the following order: Cu/AC-N-MP > Cu/AC-N-P > Cu/AC-N-IM. The microwave heated polyol process is a facile method for the rapid synthesis of carbon-supported Cu catalysts for NO removal at low temperature.