WO3-MnOx/TiO2-ZrO2催化剂脱汞性能研究

在溶胶-凝胶法制备MnOx/TiO2-ZrO2催化剂的基础上采用分步浸渍法制备WO3-MnOx/TiO2-ZrO2系列催化剂,通过BET比表面积检测法、扫描电子显微镜(SEM)、X射线衍射(XRD)、氢气程序升温还原(H2-TPR)等表征手段对该催化剂微观结构及氧化还原性能进行了相关的表征检测,并通过气固催化床对催化剂氧化脱除Hg^0的性能进行了检测。结果表明,在WO3、MnOx负载量分别为7%(质量分数,下同)、5%和TiO2与ZrO2摩尔比2∶1的条件下,制备的催化剂比表面积、孔容分别达到161.73m^2/g、0.031 7mL/g,该结构有利于Hg0吸附,同时无定形MnO2及Mn2O3的负载提升了催化剂的氧化性能,相对于MnOx/TiO2-ZrO2催化剂在200~400℃具有较高的脱汞效率,在SO2质量浓度小于1 200mg/m3时,其抗H2O、抗SO2性较好。

Study on mercury removal performance of WO3-MnOx/TiO2-ZrO2 catalysts

Based on the MnOx/TiO2-ZrO2catalyst which was prepared by sol-gel method,a series of WO3-MnOx/TiO2-ZrO2catalysts were prepared by step impregnation.The microstructure and redox properties of the catalyst were characterized by means of BET,SEM,XRD and H2-TPR,and the Hg^0 oxidation properties were tested by fixed-bed gas-solid catalytic reactor.The experimental results showed that under the conditions of WO3,MnOxloading 7%(the mass fraction,the same below),5%,TiO2and ZrO2 mole ratio 2∶1,the specific surface area of the catalyst and pore volume were 161.73m2/g and 0.031 7mL/g,respectively.The structure was beneficial to the adsorption of Hg0,the loading of amorphous MnO2and Mn2O3increased the oxiadation performance of the catalyst.Compared with MnOx/TiO2-ZrO2catalyst,the catalyst had higher oxidative mercury removal efficiency at 200-400℃,when the concentration of SO2was less than 1 200 mg/m3,the catalyst had good anti SO2and H2O poisoning performance.