摘要
通过溶胶-凝胶法合成了La-Zr-O和Ni-La-Zr-O体系催化剂,采用XRD,BET和TPR技术对其物理化学性质进行了表征,以CO2重整CH4制合成气反应为探针反应对其重整活性进行了研究。结果表明,在空气中1100℃焙烧后,La-Zr-O体系催化剂形成了单相烧绿石结构复合氧化物,对CO2重整CH4制合成气反应表现出了优良的抗积炭能力,而以镍修饰后XRD方法只测量到了单相烧绿石结构La2Zr2O7衍射峰,说明NiO很有可能以无定形的细小晶粒均匀分散在La2Zr2O7表面。值得指出的是镍修饰后的烧绿石型催化剂对CO2重整CH4制合成气反应表现出了更加优良的催化活性,同时具有一定的抗积炭能力,优于相同方法制备的Ni-ZrO2和Ni-La2O3催化剂。
La-Zr-O and Ni-Zr-O catalysts were prepared by sol-gel method and characterized by XRD,BET,TPR and catalytic activities for the reaction of CO_2 reforming of methane to synthesis gas.The results show that well-defined La_2Zr_2O_7 powders with a single-phase pyrochlore structure can be obtained at 1100 ℃ for 3 h in air and behave excellent resistance to carbon deposition for the reaction of CO_2 reforming of methane.The Ni modified Ni-La_2Zr_2O_7 catalyst obtained single-phase pyrochlore structure La_2Zr_2O_7 diffraction peaks,which proves that NiO may disperse in the surface of La_2Zr_2O_7 with the form of small amorphous crystal particles.The Ni modified Ni-La_2Zr_2O_7 catalyst shows better catalytic activity on reaction of CO_2 reforming of methane to synthesis gas at high temperature and resistance to carbon deposition than that of the Ni-ZrO_2 and Ni-La_2O_3 catalysts prepared by the same method.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2006年第z2期62-67,共6页
Journal of the Chinese Society of Rare Earths
基金
国家教育部春晖计划资助项目(Z2004-2-15028)
内蒙自然科学基金资助项目(200408020203)
关键词
烧绿石
甲烷重整
溶胶-凝胶法
合成气
稀土
pyrochlore
synthesis gas
sol-gel method
CO_2 reforming with methane
rare earths
