Preparation and characterization of La1−xKxFeO3 (x = 0–1) by self-propagating high-temperature synthesis for use as soot combustion catalyst
Preparation and characterization of La1−xKxFeO3 (x = 0–1) by self-propagating high-temperature synthesis for use as soot combustion catalyst
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DOI：
10.1016/j.jallcom.2010.04.147
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发表时间：
2011-03
影响因子：
6.2
通讯作者：
Keita Taniguchi;N. Okinaka;T. Akiyama
中科院分区：
文献类型：
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作者：
Keita Taniguchi;N. Okinaka;T. Akiyama
本文提出了La1 − xKxFeO3制备自蔓延高温合成（SHS）作为替代铂催化剂，促进柴油机碳烟燃烧。用热天平评价了11种不同钾取代比（x = 0 - 1）的自蔓延合成产物的催化性能。在产品的质量损失曲线中，T50定义为参比烟灰的重量降低到其初始重量一半时的温度。SHS处理的La 1 − xKxFeO3的BET比表面积强烈依赖于x。所有产物均表现出良好的氧化催化活性。尽管在所得产物中具有最小的比表面积（0.11m2/g），但发现La 0.9K 0.1FeO 3（x = 0.1）是具有最低T50（442 ° C）的最佳催化剂。当x> 0.2时，La1 − xKxFeO3的T50随x的增加而降低。x = 0.6和0.8的产物在它们的T50方面是第二好的催化剂。用Friedman法计算的La0.9K0.1FeO3（x = 0.1）催化剂的平均表观活化能比Pt/Al2O3催化剂的平均表观活化能低61kJ/mol。总之，钾取代的SHS掺杂La1 − xKxFeO3可以作为Pt/Al2O3的替代物用于碳烟燃烧。
This paper proposes La1−xKxFeO3prepared by self-propagating high-temperature synthesis (SHS) as an alternative to platinum catalysts for promoting diesel soot combustion. The catalytic property of eleven products SHSed with different substitution ratios of potassium (x=0–1) was experimentally evaluated using a thermobalance. In the mass loss curves of the product, T50was defined as the temperature at which the weight of the reference soot decreases to half its initial weight. The BET specific surface area of SHSed La1−xKxFeO3depended on x strongly. All the products showed good oxidation catalytic activity. Despite having the smallest surface area (0.11m2/g) among the obtained products, La0.9K0.1FeO3(x=0.1) was found to be the best catalyst with the lowest T50(442°C). T50of La1−xKxFeO3decreased with increasing x for x>0.2. The products with x=0.6 and 0.8 were the second-best catalysts in terms of their T50. Moreover, average apparent activation energy of La0.9K0.1FeO3(x=0.1) calculated by Friedman method using TG was as much as 61kJ/mol lower than that of Pt/Al2O3catalyst. In conclusion, potassium-substituted SHSed La1−xKxFeO3can be used as an alternative to Pt/Al2O3for soot combustion.