<p>This study investigated the effects of sequential acid treatment and phosphorus incorporation on the performance of Fe–Mn-Ce composite metal oxide catalysts. The FeMnCeO<sub><i>x</i></sub> catalyst was prepared using the sol–gel method and modified through two methods: treatment with phosphoric acid alone and a sequential treatment with phosphoric acid followed by sulfuric acid. The results show that the sequentially acid-treated catalyst exhibited over 90% NO<sub><i>x</i></sub> conversion and N<sub>2</sub> selectivity in the temperature range of 200–350&#xa0;°C, outperforming other catalysts. Characterization analyses such as XRD and NH<sub>3</sub>-TPD revealed that acid modification enhanced the surface acidity and redox properties of catalysts. XPS analysis showed that sequential acid treatment increased the surface chemisorbed oxygen content of the catalyst and optimized its surface structure. In-situ DRIFTS spectroscopy further elucidated that the catalytic reaction follows both Langmuir–Hinshelwood and Eley–Rideal mechanisms concurrently.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

The effect of phosphorus modification and sequential acidification on the NH3-SCR performance of composite metal oxide catalysts

  • Xinyu Li,
  • Jingqi Li,
  • Na Li

摘要

This study investigated the effects of sequential acid treatment and phosphorus incorporation on the performance of Fe–Mn-Ce composite metal oxide catalysts. The FeMnCeOx catalyst was prepared using the sol–gel method and modified through two methods: treatment with phosphoric acid alone and a sequential treatment with phosphoric acid followed by sulfuric acid. The results show that the sequentially acid-treated catalyst exhibited over 90% NOx conversion and N2 selectivity in the temperature range of 200–350 °C, outperforming other catalysts. Characterization analyses such as XRD and NH3-TPD revealed that acid modification enhanced the surface acidity and redox properties of catalysts. XPS analysis showed that sequential acid treatment increased the surface chemisorbed oxygen content of the catalyst and optimized its surface structure. In-situ DRIFTS spectroscopy further elucidated that the catalytic reaction follows both Langmuir–Hinshelwood and Eley–Rideal mechanisms concurrently.