Application of TiO2-Montmorillonite Composite Carrier in Plate-type De-NOx Catalyst
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摘要: 为提升平板式脱硝催化剂性能,以TiO2-蒙脱土、TiO2-酸改性蒙脱土为复合载体进行催化剂的制备。采用XRF、XRD、N2-吸附脱附、拉曼光谱、H2-TPR、NH3-TPD等表征手段对催化剂的物理化学性能进行分析。结果显示:与传统V2O5-MoO3/TiO2催化剂相比,采用上述复合载体制备的脱硝催化剂具有更高的比表面积和耐磨强度。V2O5-MoO3/TiO2-蒙脱土催化剂中碱金属元素(Na、K)的存在,降低了催化剂的还原性能和酸性性能,对催化剂的脱硝活性有负面影响。相比蒙脱土,酸改性蒙脱土的比表面积较高,碱金属元素含量降低,所以V2O5-MoO3/TiO2-酸改性蒙脱土催化剂的脱硝活性较高。此外,该催化剂还具备优良的抗SO2、H2O性能。Abstract: In order to improve the catalytic property of the plate-type De-NOx catalysts, TiO2-montmorillonite and TiO2-acid treated montmorillonite were used as the composite carriers for the preparation of the catalyst. XRF, XRD, N2-adsorption, Raman, H2-TPR and NH3-TPD analysis were carried out to investigate the physical and chemical properties of the catalysts. The result shows that the BET surface area and the attrition strength of the catalysts with the using of composite carriers are higher than that of the traditional V2O5-MoO3/TiO2 catalyst. Alkali metal element (Na, K) contained in the montmorillonite has negative effect on the reducibility and acidity of V2O5-MoO3/TiO2-montmorillonite catalyst, which is unfavorable for the catalytic performance. The acid treatment improves the BET surface area of the montmorillonite, and decreases the alkali metal element content simultaneously. As a result, the catalytic activity of V2O5-MoO3/TiO2-acid treated montmorillonite catalyst is relatively high. Addtionally, this catalyst also exhibits well SO2 and H2O resistance.
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Key words:
- De-NOx /
- Montmorillonite /
- Composite carrier /
- Plate-type
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表 1 不同催化剂的XRF分析结果/%
Table 1. XRF results for the different catalysts
催化剂 V2O5 MoO3 Na2O K2O MM-1 1.43 2.89 0.07 0.01 MM-2 1.45 2.86 0.11 0.21 MM-3 1.42 2.88 0.08 0.09 表 2 不同催化剂的孔结构分析数据和机械性能
Table 2. Textural properties and attrition strength of the different catalysts
催化剂 比表面积/
(m2·g-1)孔容/
(cm3·g-1)平均孔径/
nm耐磨强度/
(mg·100 r-1)TiO2 82.43 0.361 17.24 - 蒙脱土 210.22 0.364 8.09 - 酸改性
蒙脱土253.48 0.425 5.74 - MM-1 76.01 0.312 17.61 74.8 MM-2 95.91 0.339 14.26 55.4 MM-3 97.56 0.348 14.15 54.9 -
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