摘 要：为分析碱金属及碱土金属对催化剂主要活性组分V6O15分子团簇的影响，应用Gaussian软件结合密度泛函理论的B3LYP方法对V6O15分子团簇模型进行结构优化，并计算加入金属原子K、Na、Ca后钒基的分子结构参数、吸附能、LUMO轨道能量和加氢反应放热量，得出金属原子对钒基催化剂的作用机理和影响规律。结果表明：催化剂在吸附K、Na、Ca金属原子后催化活性下降；吸附碱金属后，V6O15团簇氧化性强弱顺序为：未中毒>Ca中毒>Na中毒>K中毒；V6O15团簇中毒程度的影响顺序为：K中毒>Na中毒>Ca中毒>未中毒。

Abstract: Catalyst deactivation is a complex problem encountered during the practical operation of selective catalytic reduction (SCR) technology,which leads to a lowness in catalyst denitration activity and selectivity over time.In order to study the effect of alkali metal and alkaline earth metal on the main active component V6O15 cluster,Gaussian software combined with the DFT theory at B3LYP level was used to optimize the structure and obtain the molecular structure parameters,adsorption energy,LUMO orbital energy and hydrogenation reaction of the catalyst after adsorbing the metal atom K,Na and Ca,to investigate the mechanism and influencing trends of metal atom on vanadium based catalyst.The results show that the catalytic activity decreases with the admixing of K,Na and Ca metal atoms.After adsorbing K,Na and Ca metal atoms,the order of oxidization degree is: Unpoisoned> Ca-poisoned> Napoisoned>K-poisoned,and the poisoning effect order for V6O15 cluster is: K-poisoned> Na-poisoned> Ca-poisoned> Unpoisoned.

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