摘要
To decompose efficiently hydrogen cyanide (HCN) in exhaust gas, γ-Al2O3-supported bimetallicbased Cu-Ni catalyst was prepared by incipient-wetness impregnation method. The effects of the calcination temperature, H2O/HCN volume ratio, reaction temperature, and the presence of CO or O2on the HCN removal efficiency on the Cu-Ni/γ-Al2O3 catalyst were investigated. To examine further the efficiency of HCN hydrolysis, degradation products were analyzed. The results indicate that the HCN removal efficiency increases and then decreases with increasing calcination temperature and H2O/HCN volume ratio. On catalyst calcined at 400℃, the efficiency reaches a maximum close to 99% at 480 min at a H2O/HCN volume ratio of 150. The HCN removal efficiency increases with increasing reaction temperature within the range of 100v-500℃ and reaches a maximum at 500℃.This trend may be attributed to the endothern'ficity of HCN hydrolysis; increasing the temperature favors HCN hydrolysis. However, the removal efficiencies increases very few at 500℃ compared with that at 400℃. To conserve energy in industrial operations, 400℃ is deemed as the optimal reaction temperature. The presence of CO facilitates HCN hydrolysis andincreases NH3 production. 02 substan.tially increases the HCN removal efficiency and NOx production but decreases NH3 production.
To decompose efficiently hydrogen cyanide (HCN) in exhaust gas, γ-Al2O3-supported bimetallicbased Cu-Ni catalyst was prepared by incipient-wetness impregnation method. The effects of the calcination temperature, H2O/HCN volume ratio, reaction temperature, and the presence of CO or O2on the HCN removal efficiency on the Cu-Ni/γ-Al2O3 catalyst were investigated. To examine further the efficiency of HCN hydrolysis, degradation products were analyzed. The results indicate that the HCN removal efficiency increases and then decreases with increasing calcination temperature and H2O/HCN volume ratio. On catalyst calcined at 400℃, the efficiency reaches a maximum close to 99% at 480 min at a H2O/HCN volume ratio of 150. The HCN removal efficiency increases with increasing reaction temperature within the range of 100v-500℃ and reaches a maximum at 500℃.This trend may be attributed to the endothern'ficity of HCN hydrolysis; increasing the temperature favors HCN hydrolysis. However, the removal efficiencies increases very few at 500℃ compared with that at 400℃. To conserve energy in industrial operations, 400℃ is deemed as the optimal reaction temperature. The presence of CO facilitates HCN hydrolysis andincreases NH3 production. 02 substan.tially increases the HCN removal efficiency and NOx production but decreases NH3 production.
基金
Acknowledgements This work is financially supported by the National Natural Science Foundation of China (Grant No. 21277064), and the Scientific Research Key Project Fund of Ministry of Education (No. 210202).