摘要
用柠檬酸络合法制取了LaMO_3(M=Cr,Fe,Co,Ni)与La_(1-x)Sr_xFeO_3(x=0.1～0.4)系列化合物。X射线衍射(XRD)分析表明,LaMO_3(M=Cr,Fe,Co,Ni)与La_(1-x)Sr_xFeO_3(x=0.1～0.3)均为单相钙钛矿型复合氧化物;x=0.4时,有少量SrFeLaO_4与钙钛矿相共存。在300～500℃范围内水蒸汽转化反应催化活性顺序为:LaCoO_3>LaNiO_3>LaFeO_3>LaCrO_3,400℃时La_(1-x)Sr_xFeO_3系催化活性随x值的递增而下降。上述活性变化规律与催化剂晶格中氧结合能有关,晶格氧结合能愈低,催化活性愈好。文中对钙钛矿型催化剂上水汽转化反应的机理作了初步探讨。
A series of LaMO_3(M=Cr,Fe,Co,Ni)and La_(1-x)Sr_xFeO_3(x=0.1～0.4)Compounds were synthesised by complexing method incitric acid. X-ray diffraction (XRD) indicated that the. mixed oxides are the single phase perovsk-ire in structure, When x≤0.3, and in the acse of x=0.4, the SrFeLao_4 pho-se appeared together with the perovskite phase. The catalytic activities of the samples LaMO_3 for water-gas shift reaction in 300～500 C have been determined and have the following order: LaCoO3>LaNiO_3>LaFeO_3>LaCrO_3; and theactivities of La_(1-x)Sr_xFeO_3 at 400℃ decreased with increasing the x Value. It seems that the activity for water-gas shift increases with the decreasing of the binding energy of the Lattice oxgven in LaMO_2 and La(?)Sr(?)FeO(?)(x=0 1～0 3)
出处
《宁夏大学学报（自然科学版）》
CAS
1993年第4期60-63,共4页
Journal of Ningxia University(Natural Science Edition)
关键词
钙钛矿型
催化剂
水汽转化反应
water-gas shift reaction, perovsite- type oxides catalysts.
