| 摘要: |
| 以硝酸钴和硝酸镧等为原料在碱性条件下共沉淀制备出LaCoO3钙钛矿复合氧化物,通过XRD、SEM、XPS及N2吸附-脱附等方法证实LaCoO3基本粒径为80～120 nm,比表面积为9.0 m2/g。在高压釜中以LaCoO3钙钛矿为催化剂,以氧气为氧源,研究以异丁醛为催化助剂、N,N-二甲基甲酰胺(DMF)为溶剂的环己烯环氧化过程。结果表明:在pH=8,20 ℃常温沉淀,焙烧温度为700 ℃和焙烧时间为4 h的条件下制备的LaCoO3钙钛矿复合氧化物催化剂的催化活性最高;在催化剂质量为0.2 g、环己烯质量为2.0 g、氧气压力为4 MPa、反应温度为50 ℃、反应时间为5 h的条件下,环己烯转化率达到64.9％,环氧环己烷的选择性达到68.6％。 |
| 关键词: 钙钛矿 环己烯 催化氧化 分子氧 沉淀 选择性 |
| DOI：10.3969/j.issn.1673-5005.2021.02.019 |
| 分类号::TQ 426.8 |
| 文献标识码:A |
| 基金项目: |
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| Epoxidation of cyclohexene on LaCoO3 perovskite oxides |
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SHI Bin, ZHANG Bin, ZHANG Xuelong, LIU Huan, QIAN Yanghui, RUAN Xiaoyun, LI Zhongtao
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(State Key Laboratory of Heavy Oil Processing in China University of Petroleum (East China), Qingdao 266580, China)
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| Abstract: |
| The LaCoO3 perovskite composite oxides were prepared with Co(NO3)2 and La(NO3)2 under alkaline condition by coprecipitation. The oxides were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), N2 adsorption-desorption. It is found that the basic particle size of LaCoO3 perovskite is 80-120 nm and the specific surface area is 9.0 m2/g. The catalytic epoxidation of cyclohexene was conducted in an autoclave with LaCoO3 perovskite, O2 as oxidant, isobutyraldehyde as catalytic auxiliary, and N,N-dimethyl formamide (DMF) as solvent. The results show that the LaCoO3 perovskite prepared by coprecipitation could achieve the highest activity under the conditions of pH=8,20 ℃ of precipitation temperature, calcination temperature of 700 ℃ and calcination time of 4 h. The best catalytic epoxidation condition is O2 pressure 4 MPa, reaction temperature 50 ℃, reaction time 5 h with catalyst mass 0.2 g and cyclohexene mass 2.0 g. The conversion of cyclohexene and the selectivity of epoxycyclohexane could reach 64.9％ and 68.6％, respectively. |
| Key words: perovskite cyclohexene catalytic oxidation molecular oxygen precipitation selectivity |
