沉淀/络合剂对六铝酸盐-氧化铝复合涂层结构及粘附性能的影响  

Study on influence of precipitates/complexants on structures and adhesion stabilities of hexaaluminate-alumina composite layer

作　　者：陈丹[1] 张立红[1] 刘源[1] 

机构地区：[1]天津大学化工学院,天津300072

出　　处：《化工新型材料》2014年第8期73-75,91,共4页New Chemical Materials

基　　金：国家自然科学基金(20901056);天津市自然科学基金(11JCYBJC04000);天津大学自主创新基金(1002029)

摘　　要：以γ-Al2O3/FeCrAl为基体并提供铝源,采用静态碱络合法制备了镧锰六铝酸盐(LaMn-hexaaluminate,简写LHA)-氧化铝复合涂层LHA-Al2O3。研究了不同沉淀/络合剂(氨水、氢氧化钠、碳酸铵、尿素、乙二胺)对涂层结构、形貌和粘附稳定性能的影响。采用SEM,XRD等对涂层的结构和形貌进行了表征,采用超声波振荡和热冲击对LHAAl2O3/FeCrAl及LHA/LHA-Al2O3/FeCrAl的粘附性能进行了测试,并对催化剂进行了甲烷催化燃烧活性测试。结果表明5个样品的活性结果相近,而氨水样品的粘附性能最好,尿素样品粘附性能最差。说明在保障良好甲烷催化燃烧的前提下,过渡层中嵌入和覆盖的板状LHA颗粒决定了催化剂体系的粘附稳定性。A composite layer of LaMn-hexaaluminate（LHA） in situ embedding in alumina layer （denoted as LHA- Al2 O3 ） was developed with the γ-Al2 O3/FeCrAl foil as both substrate and aluminum source by static precipitation method. The influences of precipitates/complexants （ammonia, sodium hydrate,ammonium carbonate,urea, ethidene diamine） were investigated. The structure and morphology of the catalysts were characterized using XRD and SEM. The processes of ultrasonic vibration and thermal shock were conducted to evaluate the adhesion stability,and the catalytic combustion of CH4 was performed to evaluate the catalytic activity of LHA-Al2O3/FeCrAI and LHA/LHA-Al2O3/FeCrAl. The results showed that the five samples had similar activity results, while sample of amonia showed the best adhesion stability and sample of urea showed the worst. It can be concluded that on the basis of maintaining good catalytic activity of CH4 com- bustion, the plate-like LHA grains embedding in and covering on the intermediate layer determined the adhesion stability of the monolithic catalysts.

关 键 词：六铝酸盐 沉淀 络合剂 复合涂层 原位制备 粘附性能 

分 类 号：O611.3[理学—无机化学] TQ630.1[理学—化学]