LaFe_(x)Al_(12)-xO_(19)六铝酸盐催化剂上氨分解制氢性能  

Hydrogen production from ammonia decomposition over LaFe_(x)Al_(12)-xO_(19) hexaaluminate catalysts

作　　者：赵雅绪 张凤莲 段潇潇 蒋国霞 徐欣 郝郑平 周华荣[1] ZHAO Yaxu;ZHANG Fenglian;DUAN Xiaoxiao;JIANG Guoxia;XU Xin;HAO Zhengping;ZHOU Huarong(Xinjiang Institute of Ecology and Geography,Urumchi,830011,China;Research Center for Environmental Material and Pollution Control Technology,University of Chinese Academy of Sciences,Beijing,101408,China;National Engineering Laboratory for VOCs Pollution Control Material&Technology,Beijing,101408,China)

机构地区：[1]中国科学院新疆生态与地理研究所,乌鲁木齐830011 [2]环境材料与污染控制技术研究中心,中国科学院大学,北京101408 [3]挥发性有机物污染控制材料与技术国家工程实验室,北京101408

出　　处：《环境化学》2022年第7期2170-2179,共10页Environmental Chemistry

基　　金：山东省重大科技创新工程项目(2019JZZY010506);国家自然科学基金(21976176、22006148);中央高校基本科研业务费专项资金资助

摘　　要：采用并流共沉淀法制备了系列Fe取代的LaFe_(x)Al_(12-x)O_(19)(LaFex,其中x=0,2,4,6,8)六铝酸盐催化剂,分别考察了Fe取代量、反应温度、空速对NH_(3)分解反应活性的影响。研究结果表明,升高温度有利于提高NH_(3)的转化率;NH_(3)分解反应活性随着Fe取代量的增加先增加后降低,其中LaFe_(4)具有最佳的催化性能,在550℃即可实现NH_(3)的完全转化,并能稳定运行50 h以上。采用X射线衍射仪(XRD)、氮气吸脱附(BET)、程序升温还原(TPR)和X射线光电子能谱(XPS)等技术手段对催化剂进行了表征,结果表明,氨分解活性应该与反应温度、催化剂的氧化还原性能以及催化剂中八面体配位的Fe^(3+)的数量密切相关。A series of Fe-substituted LaFe_(x)Al_(12-x)O_(19)(where x=0,2,4,6,8)catalysts were prepared by the co-precipitation method,and the impacts of Fe substitution,reaction temperature and space velocity on reaction activity were investigated.The research results showed that raising temperature was beneficial to improve the conversion of NH_(3).Meanwhile,the activity of NH3 decomposition increased firstly and then decreased accompanied with the augment of Fe substitution.LaFe_(4) catalyst exhibited the best catalytic performance among the catalysts,which could achieve complete conversion of NH3 at 550°C and run stably for more than 50 h.X-ray diffraction(XRD),N2 adsorption-desorption(BET),Temperature programmed reduction(TPR)and X-ray photoelectron spectroscopy(XPS)were used to characterize the catalysts.The research results showed that the activity of NH_(3) decomposition is closely related to the reaction temperature,redox ability of the catalysts and the amounts of Fe3+in octahedral coordination in the catalysts.

关 键 词：氨分解 制氢 Fe取代六铝酸盐 催化性能 活性相 

分 类 号：TQ116.2[化学工程—无机化工] TQ426