摘要
采用 XRD,TPD和高温原位 IR光谱对 La2 O3,Ba O/La2 O3,Ba F2 /La2 O3,La OF和 Ba F2 /La OF等催化剂的组成、结构和 CO2 在催化剂上的吸附状况进行了表征 ,并结合催化剂性能评价结果对该系列催化剂的碱性及其与 OCM反应性能的关系进行了考察 .结果表明 ,催化剂
The structure and surface basicity of a series of lanthanum based catalysts (La 2O 3, BaO/La 2O 3, BaF 2/La 2O 3, LaOF, BaF 2/LaOF) were characterized by XRD, CO 2 TPD and high temperature in situ FTIR spectroscopy of CO 2 adsorption. Both the results of CO 2 TPD and in situ FTIR spectra of CO 2 adsorption indicate that the basicity of the catalysts decreases in the sequence BaO/La 2O 3>La 2O 3>BaF 2/La 2O 3>BaF 2/LaOF>LaOF. The experiments of catalytic performance evaluation of the catalysts performed at 800 ℃ under the conditions of V (CH 4)/ V (O 2)=4 and GHSV= 15 000 h -1 indicate that the BaF 2 modified La 2O 3 and LaOF demonstrate a better OCM performance compared to the corresponding La 2O 3 and LaOF. These observations suggest that the surface basicity is not always a requisite attribution for a good OCM catalyst.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2000年第4期575-580,共6页
Chemical Journal of Chinese Universities
基金
国家重点基础研究发展规划项目 !(批准号 :G19990 2 2 40 8)
福建省自然科学基金 !(批准号 :B970 0 1)
关键词
镧基催化剂
甲烷氧化偶联
碱性
催化性能
Lanthanum based catalysts
Oxidative coupling of methane
Basicity
CO 2 adsorption
in situ IR
TPD
