Nitrate nonahydrate

The Sm-promoted catalysts were prepared by the co-precipitation method. A solution containing iron(iii) nitrate nonahydrate (>99.99 wt% Shanghai Macklin Biochemical Co., Ltd), manganese nitrate (50 wt% Shanghai Macklin Biochemical Co., Ltd) and samarium(iii) nitrate hexahydrate (>99.99 wt% Shanghai 3A Chemical Co., Ltd) with the desired ratio was precipitated by anhydrous sodium carbonate (>99.99 wt% Shanghai Macklin Biochemical Co., Ltd) at 65 °C. The pH value of the solution was kept at 8.0 ± 0.3. Then, the solution was stirred for 0.5 h and aged for 1 h. After washing, filtration and drying, the precipitate was treated at 550 °C for 3 h. The FeMnSm catalysts were prepared by the above methods. The molar compositions of the catalysts were 100Fe/10Mn/xSm (x = 0, 0.5, 1, 1.5 and 2), which were labeled as Sm0, Sm0.5, Sm1, Sm1.5 and Sm2, respectively.

Iron(iii) nitrate nonahydrate (>99.99 wt% Shanghai Macklin Biochemical Co., Ltd), manganese nitrate (50 wt% Shanghai Macklin Biochemical Co., Ltd), samarium(iii) nitrate hexahydrate (>99.99 wt% Shanghai 3A Chemical Co., Ltd) and anhydrous sodium carbonate (>99.99 wt% Shanghai Macklin Biochemical Co., Ltd) were purchased. Deionized water was used for all experiments.