High efficient removal of HCN over porous CuO/CeO2 micro-nano spheres at lower temperature range

Abstract

The porous CeO2 flowerlike micro-nano spheres based materials were prepared to remove HCN effectively at lower temperature range. The CeO2 and a serious of porous flowerlike ceria based materials loaded with metal species including Cu, Ag, Ni, Co and Fe were synthesized by hydrothermal method and precipitation method respectively. The physicochemical properties were probed by means of XRD, H2-TPR, BET, SEM and XPS. The removal ability for 130 mg·m−3 HCN over CuO/CeO2 showed the highest activity, the breakthrough time of which was more than 70 min at the condition of 30 °C, 120,000 h−1 and 5 % (volume) H2O, owe to a higher relative atomic ratio of oxygen vacancies and Oβ, the stronger interaction between metal particle and support, the optimum redox properties. The reaction mechanism was speculated by detecting the reaction products selectivity at different reaction temperature. It was shown that the reaction system for removal of HCN over CuO/CeO2 catalytic material involved chemisorption, catalytic hydrolysis, catalytic oxidation as well as NH3-SCR reactions.