【摘要】 实验室制备了V2O5-WO3/TiO2的脱硝催化剂,采用模拟中毒法,在此催化剂上负载碱金属氧化物K2O,通过BET,XRD,SEM等方法对微观结构进行表征.在SCR活性试验台上研究不同含量K2O对催化剂脱硝活性,N2O生成率和SO2氧化率的影响.结果发现:K2O对于催化剂的毒性较强,随着添加量的增大,NO脱除率急剧下降,SO2的氧化率大大提高;较大含量的K2O(nK/nV=1,摩尔比)使催化剂比表面积有所减少,催化剂颗粒发生轻微团聚,微观结构变化不大,但NO的脱除率小于50%(380℃),N2O的生成率和SO2的氧化率均增加;K2O通过与V2O5的活性酸性位结合,使催化剂中有效活性位数量大为降低,导致脱硝活性下降.更多还原

【Abstract】 V2O5-WO3/TiO2 catalysts were prepared and K2O were added on them by simulated poisoning method.To investigate the micro structure of catalyst BET(brurauer-emmett-teller),XRD(X-ray diffraction),and SEM(scanning electron microscope) were employed.Effect of K2O on the DeNOx activity,N2O generation and SO2 oxidation were studied using SCR activity reactor.It has been found that K2O has strong poisoning effect on the catalyst.NO removal efficiency is decreased and SO2 oxidation ratio is increased along with the increase of K2O.When nK/nV=1(mole ratio),surface area of catalyst-BET is decreased,particles aggregate lightly,and there are some changes in micro structure,but NO removal efficiency less than 50%(380 ℃),N2O generation and SO2 oxidation are increased.Depletion of DeNOx efficiency of the catalyst is caused by acid sites of V2O5 bonded with K2O which results in the decrease of the quantity of acid sites.更多还原