摘要
研究了甲烷氧化偶联制乙烯高选择性Ｌａ２Ｏ３－ＢａＯ体系催化剂的稳定性．在８００℃、ＣＨ４空速１００００ｈ－１、ＣＨ４／Ｏ２＝８．０～８．３的条件下，催化剂稳定运转了５００ｈ，ＣＨ４转化率和Ｃ２选择性分别为≥１８％和≥８０％．ＸＲＤ和ＸＰＳ分析表明，该催化剂物相稳定，表面Ｌａ／Ｂａ原子浓度之比随反应时间的增加而稍有增加，有利于催化剂活性和选择性的稳定．
おhe stability of high C_2 selectivity catalyst of La_2O_3BaO for OCM has been investigated. The activity and selectivity of the catalyst kept steady after a 500 h continuous test, with the CH_4 conversion and C_2 selectivity being ≥ 18% and ≥ 80%, respectively, under the condition of T=800℃, CH_4/O_2=8.0￣8.3 and space velocity of CH4: 10000 h-1. The total of CH_4 conversion and C_2 selectivity were stable between 98% and 100%. The analysis of XRD and XPS showed that the phase composition was stable while the surface Li^3+/Ba^2+ atom concentration ratio rose smoothly with the increase of reaction time, which was beneficial for the stability of catalyst.
出处
《分子催化》
EI
CAS
CSCD
北大核心
1998年第2期129-132,共4页
Journal of Molecular Catalysis(China)
关键词
甲烷
氧化偶联
催化剂
制备
乙烯
镧
Oxidative coupling of methane, High selectivity catalyst, Stability, La_2O_3BaO system
