摘要
用共沉淀法与浸渍法制备的ThO_(2-)La_2O_(3-)BaCO_3三组分复合物催化剂在反应温度600℃ ,催化剂床层热点温度665℃的条件下,采用甲烷/空气共进料方式,可以获得22.4%甲烷转化率和64.6%C_2烃选择性,本文考察了各组分含量对催化性能的影响,用离子阱在线检测考察了在纯ThO_2与三组分复合物催化剂上CO脉冲反应的差别.
This paper reports a new catalyst for oxidative coupling of methane with 22. 4% conversion of methane and 64. 8% C2 hydrocarbon selectivity at reaction temperature 600℃ (665℃ hot spot temperature). The components of the catalyst are ThO2-La2O3/BaCO3. It was prepared by two steps. The first step was to prepare a La2O3/ BaCO3 precursor using copricipitation, the second step is to impregnate thorium nitrate on the dried La2O3/BaCO3, followed by drying, then calcining in air at 700℃ for 4-6 h. The spicific surface area of the catalyst is 5. 6 m2/g. The XRD patterns showed only two peaks d = 3. 064 and d=l. 643 attributable to La4ThO8new phase, other peaks are due to each of the components.
CO is not formed in the reaction of OCM over this catalyst. The results of CO pulse reaction showed that CO reacts with the lattice or irreversibly adsorbed oxygen to CO2. The effect of temperature by temperature programmed reaction demonstrates that the reaction is mainly deep oxidation at lower temperature (530℃) and the selectivity of C2 hydrocarbons increases with the elevation of temperature.
出处
《分子催化》
EI
CAS
CSCD
1993年第2期134-140,共7页
Journal of Molecular Catalysis(China)
基金
甘肃省自然科学基金资助课题
关键词
氧化
甲烷
催化剂
催化
活性
Oxidative coupling, Methane, Catalyst, Thoria, Lanthanum oxide, Barium carbonate.
