Optimization of Cu/activated carbon catalyst in low temperature selective catalytic reduction of NO process using response surface methodology

Abstract

Preparation of Cu/Activated Carbon (Cu/AC) catalyst was optimized for low temperature selective catalytic reduction of NO by using response surface methodology. A central composite design (CCD) was used to investigate the effects of three independent variables, namely pre-oxidization degree (HNO₃%), Cu loading (wt.%) and calcination temperature on NO conversion efficiency. The CCD was consisted of 20 different preparation conditions of Cu/AC catalysts. The prepared catalysts were characterized by XRD and SEM techniques. Predicting NO conversion was carried out using a second order model obtained from designed experiments and statistical software Minitab 14. Regression and Pareto graphic analysis showed that all of the chosen parameters and some interactions were effective on the NO conversion. The optimal values were pre-oxidization in 10.2% HNO₃, 6.1 wt.% Cu loading and 480°C for calcination temperature. Under the optimum condition, NO conversion (94.3%) was in a good agreement with predicted value (96.12%).

Keywords:

• NOx
• low temperature
• SCR
• activated carbon
• RSM
• optimization.

Acknowledgments

The authors would like to gratefully acknowledge Iranian Nanotechnology Initiative and University of Tabriz, Iran, for encouragement and support.