Sm doped NiO catalysts with excellent H2O resistance for N2O decomposition under simulated nitric acid plant exhaust condition

Abstract

Sm0.06Ni with excellent H2O resistance for eliminating N2O was prepared by co-precipitation method. Research indicated that the introduction of Sm into Sm0.06Ni has the following effects: (1) Sm species (Sm2O3) highly dispersed on the surface of Sm0.06Ni catalyst, which not only decreased the crystallite size of NiO, but also produced a certain number of edge dislocations and defects. (2) Sm2O3 weakened the Ni-O band and increased the number of active sites. (3) The redox cycle of Ni2+ + Sm3+ ↔ Ni3+ + Sm2+ was formed on the surface of Sm0.06Ni during the reaction. Based on the above changes, Sm0.06Ni exhibited superior catalytic performance and much lower Ea for the reaction compared with pure NiO. Over Sm0.06Ni, the TOF at 350 ℃ was 4.1 × 10−3 s−1, 37 times of that over pure NiO. More importantly, Sm0.06Ni exhibited excellent H2O resistance performance under submitted real reaction conditions, about 76 % N2O conversion can be obtained at 400 ℃.