摘要
为解决蜂窝堇青石载体比表面积小、活性组分难以负载等问题,采用硝酸酸蚀堇青石载体并负载金属氧化物,制备了Cu-Mn-Ce/堇青石催化剂.分析了不同酸蚀强度下催化剂对甲苯催化燃烧差异的原因,在40%wt硝酸溶液中、50℃下酸蚀4 h条件下得到的催化剂对甲苯的催化性能最佳,与其他催化剂相比,其表面平均孔径为38.31 nm并有更佳的孔隙率,且在12—14 nm处以及20—30 nm处有更佳的孔径分布,其上活性组分分布极为分散,具有更小的活性颗粒尺寸.在与未经酸蚀预处理催化剂的比较中发现,经酸蚀预处理的催化剂具有更大的比表面积和多样的氧化物晶体类型,更高的Cu/Mn比例(1.72∶1.26),其中Mn^(4+)(31.1%)、Ce^(3+)(27.5%)及O_(sur)(50.9%)在其占比均高于未经酸蚀预处理催化剂.
Cu-Mn-Ce/cordierite catalyst was prepared by etching cordierite carrier with nitric acid and loading metal oxides in order to solve the problems of low specific surface area of cordierite carrier and difficult loading of active components.The reasons for the difference in catalytic combustion of toluene under different acid etching intensities were analyzed.The catalyst obtained under the condition of 40%wt nitric acid solution and 4 h acid etching at 50℃had the best catalytic performance for toluene.Compared with other catalysts,the average surface pore size of the catalyst was 38.31 nm and the porosity was better.Moreover,the pore size distribution at 12—14 nm and 20—30 nm is better,and the active component distribution on the pore size is very dispersed,and the active particle size is smaller.Compared with the catalyst without acid etching,the catalyst treated by acid etching has larger specific surface area,diversified oxide crystal types,higher Cu/Mn ratio(1.72:1.26).Mn^(4+)(31.1%),Ce^(3+)(27.5%)and O_(sur)(50.9%)were higher than those without acid etching.
作者
李明昕
陶婉毅
任帅康
卜龙利
LI Mingxin;TAO Wanyi;REN Shuaikang;BU Longli(School of Environmental and Municipal Engineering,Xi’an University of Architecture and Technology,Xi’an,710055,China;Key laboratory of Northwest Water Resources,Environment and Ecology,Ministry of Education,Xi’an,710055 China;Key Laboratory of Environmental Engineering of Shanxi Province,Xi’an,710055,China)
出处
《环境化学》
CAS
CSCD
北大核心
2023年第7期2456-2466,共11页
Environmental Chemistry
基金
陕西省自然科学基金(2021JM-364)资助.
关键词
酸蚀
堇青石
催化性能
甲苯
微波
表征.
acid etching
cordierite
catalytic performance
toluene
microwave
characterization.
