Catalytic decomposition of N2 O over Mg-Co and Mg-Mn-Co composite oxides

作者：ZHENG Li; WU Cang cang; XU Xiu feng

来源：燃料化学学报, 2016, 44(12).

DOI：10.3969/j.issn.0253-2409.2016.12.013

• catalytic decomposition of N2 O
• Mg-Co composite oxides
• Mg-Mn-Co composite oxides
• K-modified catalysts
• catalytic performance

Mg-Co and Mg-Mn-Co composite oxides with different compositions were prepared by sol-gel method for N2 O catalytic decomposition in the presence of oxygen. Of Mg-Mn-Co catalysts, the one with higher activity was impregnated by K2 CO3 solution to make K-modified catalyst. These catalysts were characterized by X-ray diffraction ( XRD ) , nitrogen physisorption ( BET ) , scanning electron microscopy ( SEM ) , temperature-programmed reduction of hydrogen(H2-TPR), and temperature-programmed desorption of oxygen(O2-TPD). The effect of preparation parameters such as compositions and potassium loadings on their catalytic activity has been investigated. The results show that K-modified catalysts exhibit better activity and higher resistance towards water in contrast to un-modified catalyst due to the weakness of surface metal-oxygen bonds. Among these catalysts, 0. 02K/MgMn0. 2 Co1. 8 O4 is the most active, over which 97% and 60% conversions of N2 O can be reached at 400 ℃ after continuous running for 50 h under the atmosphere of oxygen-alone and oxygen-steam together, respectively. When the steam is switched off, the catalytic activity of 0. 02K/MgMn0. 2 Co1. 8 O4 can be restored to large extent, indicating the good water-resistance of K-modified catalyst.

• 单位
  化学化工学院; 烟台大学