SiO2改性的V2O5-MoO3/TiO2催化剂抗碱中毒性能研究

摘要

以陶瓷为骨架,用溶胶凝胶法和浸渍法制备了V2O5-MoO3/TiO2催化剂,并用SiO2进行改性.采用浸渍法模拟碱K中毒,研究了SiO2改性前后催化剂中毒脱硝效率的变化,并通过BET、H2-TPR、NH3-TPD等技术手段对催化剂进行了表征.结果表明,加入SiO2后,催化剂的比表面积明显提高.SiO2改性后新鲜催化剂还原温度向低温方向迁移10℃左右,氧化还原能力得到了提高,其表面酸强度和酸量也得到较大的提高.反应评价结果表明,SiO2改性可以提高催化剂抗碱中毒的件能.%V2O5-MoO3/ TiO2 catalyst was prepared by sol-gel and impregnation method and modified with SiO2 to improve its alkali-resistant performance. The alkali poisoning was simulated by the immersion of the catalyst in alkali salt solution. The effect of SiO2 modification on the de-Nox activity of V2O5-MoO3/ TiO2 catalyst in the selective catalytic reduction was investigated. BET, H2-TPR and NH3-TPD measurements indicated that the specific surface area, the redox ability (the reduction temperature is decreased by 10 t) and the acidity of the SiO2-modified V2O5-MoO3/TiO2 catalyst are increased obviously. As a result, the alkali-resistant performance of V2O5-MoO3/ TiO2 catalyst was improved largely by the SiO2 modification.