Investigation of the effect of Ce on the K resistance of V-Mo/Ti de-NOx catalyst
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摘要: 为增强工业V-Mo/Ti脱硝催化剂的抗K中毒性能,对其进行Ce改性。采用XRD、SEM、N2-吸附脱附、H2-TPR、XPS、NH3-TPD、NH3-DRIFTS等表征手段,分析了催化剂的物理性质和化学性质。使用固定床微型反应器,研究了Ce对V-Mo/Ti催化剂脱硝性能、抗K中毒性能的影响。结果显示:Ce的引入,增加了V-Mo/Ti催化剂的脱硝活性。同时,减轻了V-Mo/Ti催化剂因K中毒所引起的比表面积、还原性能、Oα/(Oα+Oβ)比率、酸性的下降。V-Mo-Ce-K/Ti催化剂的脱硝活性明显优于V-Mo-K/Ti催化剂,即Ce有效增强了V-Mo/Ti催化剂的抗K中毒性能。
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关键词:
- V-Mo/Ti脱硝催化剂 /
- 抗K中毒性能 /
- Ce改性 /
- 比表面积
Abstract: Industrial V-Mo/Ti catalyst for denitrification was modified by Ce in order to enhance its resistance to K. XRD, SEM, N2-adsorption/desorption, H2-TPR, XPS, NH3-TPD, and NH3-DRIFTS analyses were used to characterize the physiochemical properties of the different catalysts. Subsequently, the influence of Ce on the catalytic performance and K resistance of V-Mo/Ti catalyst was studied by a fix-bed micro-reactor. The results show that the presence of Ce can enhance the catalytic activity of V-Mo/Ti catalyst, and effectively reduce the negative impact of K on the BET surface area, reducibility, Oα/(Oα+Oβ) ratio, and acidity of V-Mo/Ti catalyst. The catalytic activity of V-Mo-Ce-K/Ti catalyst is higher than that of the V-Mo-K/Ti catalyst. In other words, Ce enhances the K resistance of V-Mo/Ti catalyst.-
Key words:
- V-Mo/Ti de-NOx catalyst /
- K resistance /
- modified by Ce /
- specific surface area
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表 1 不同催化剂的粒径分析数据
Table 1. Distribution of particle size of different catalysts
催化剂 D10/nm D50/nm D90/nm V-Mo/Ti 0.78 0.95 1.13 V-Mo-Ce/Ti 0.77 0.93 1.12 V-Mo-K/Ti 0.81 0.99 1.20 V-Mo-Ce-K/Ti 0.79 0.96 1.17 表 2 不同催化剂的孔结构分析数据
Table 2. Textural property of different catalysts
催化剂 比表面积/(m2·g−1) 孔容/(cm3·g−1) 平均孔径/nm V-Mo/Ti 82.1 0.34 16.6 V-Mo-Ce/Ti 79.2 0.32 17.1 V-Mo-K/Ti 66.9 0.27 17.9 V-Mo-Ce-K/Ti 72.4 0.29 17.5 表 3 不同催化剂的XPS分析数据
Table 3. XPS analysis data of different catalysts
催化剂 V5+/(V3++V4++V5+) Oα/(Oα+Oβ) Ce3+/(Ce3++Ce4+) V-Mo/Ti 0.26 0.14 V-Mo-Ce/Ti 0.29 0.16 0.29 V-Mo-K/Ti 0.22 0.10 V-Mo-Ce-K/Ti 0.26 0.13 0.24 -
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