水热法制备氧化铬及其常温低浓度一氧化氮催化性能  

Hydrothermal Fabrication and Catalytic Performance of Chromium Oxide for Low-concentration NO Oxidation at Ambient Temperature

作　　者：吴美健[1] 高振源[2] 袁静[2] 赵昆峰[2] 蔡婷[2] 杨玲[2] 张涛[2] 何丹农[1,2] 

机构地区：[1]上海交通大学材料科学与工程学院,上海200240 [2]纳米技术及应用国家工程研究中心,上海200241

出　　处：《无机材料学报》2016年第11期1191-1197,共7页Journal of Inorganic Materials

基　　金：国家973项目(20103CB933200)~~

摘　　要：以十六烷基三甲基溴化铵(CTAB)为模板剂,氨水为沉淀剂,通过水热法并焙烧处理合成氧化铬催化剂。采用X射线衍射分析(XRD)、傅里叶变换红外光谱(FT-IR)、X射线光电子能谱(XPS)和透射电镜(TEM)等技术对催化剂的物化性质进行了表征,并考察常温不同NO初始浓度下氧化铬催化剂的NO氧化性能。结果表明:在空速为60000 m L/(g·h)和NO浓度为1×10^(-6)的条件下,100℃水热温度制备的Cr-100催化剂表现出最优的性能,常温下NO消除率高达90%以上并保持120 h,其优异的常温催化性能与催化剂表面较高的Cr^(6+)/Cr^(3+)摩尔比有关。研究结果表明:催化剂的失活主要是由于硝酸根在催化剂表面的累积而导致催化剂活性中心被覆盖,低浓度下能减缓硝酸根的积累。The chromic oxide catalysts were synthesized by hydrothermal method using CTAB as surfactant and NH3.H20 as precipitant. Physiochemical properties of these catalysts were characterized by X-ray diffraction （XRD）, Fourier Transform lufrared specfroscopy （FT-IR）, X-ray photoelectron spectroscope （XPS）, and transmission electron microscope （TEM）. The catalytic NO removal performances for different NO concentrations at room temperature was also investigated. It was shown that under the conditions of space velocity of 60, 000 mL/（g.h） and NO concentration of 1 × 106, sample of Cr-100 exhibited the best catalytic performance, which maintained 120 h as removal ratio of NO more than 90%. This excellent catalytic performance could be attributed to the surface ions ratio of Cr6＋/Cr3＋. The FT-IR analysis indicated that catalyst deactivation was due to the active sites of chromic oxide occupied by nitrates, consistent with the results of XPS. Furthermore, the activity tests in different conditions demonstrated that low NO concentration could slow down the rate of nitrate accumulation and prolong the catalyst lifetime.

关 键 词：水热法 常温 失活 氧化铬 

分 类 号：X511[环境科学与工程—环境工程]