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乙烷干重整 1

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High-precision diffusion measurement of ethane and propane over SAPO-34 zeolites for methanol-to-olefin

Dali Cai, Yu Cui, Zhao Jia, Yao Wang, Fei Wei

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 77-82 doi: 10.1007/s11705-017-1684-5

摘要： The methanol-to-olefin (MTO) process has attracted much attention and many problems including lifetime and selectivity of light olefins have all been connected to the diffusion problems in zeolite crystals. However, a quantitative study of diffusion problems in SAPO-34 zeolites is lacking. In this paper, we performed a high-precision diffusion measurement of the diffusion behavior of ethane and propane, which represent ethylene and propylene respectively, over SAPO-34. The diffusions of ethane and propane over fresh and coked SAPO-34 zeolites with different crystal sizes were carefully studied. Ethane and propane show different diffusion behavior in SAPO-34. The diffusion of ethane is almost not influenced by the crystal size and coke percentage, whereas that of propane is strongly affected. A slower diffusion velocity was observed in bigger crystals, and the diffusion velocity decline significantly with the coke percentage increasing. The diffusion coefficient was calculated with both the internal and surface diffusion models, and the results show that the surface diffusion plays a key role in the diffusion process of both ethane and propane. We believe that this work would be helpful for understanding the diffusion of different molecules in SAPO-34 zeolites, and may lay the foundation of MTO research.

关键词： diffusion measurement methanol-to-olefin process

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Light olefins synthesis from С

Anton SHALYGIN, Evgenii PAUKSHTIS, Evgenii KOVALYOV, Bair BAL’ZHINIMAEV

《化学科学与工程前沿（英文）》 2013年第7卷第3期页码 279-288 doi: 10.1007/s11705-013-1338-1

摘要： A two-step process was employed to convert methane or ethane to light olefins via the formation of an intermediate monoalkyl halide. A novel K RuOCl /TiO catalyst was tested for the oxidative chlorination of methane and ethane. The catalyst had high selectivity for methyl and ethyl chlorides, 80% and 90%, respectively. During the oxychlorination of ethane at ≥250°C, the formation of ethylene as a reaction product along with ethyl chloride was observed. In situ Fourier transform infrared studies showed that the key intermediate for monoalkyl chloride and ethylene formation is the alkoxy group. The reaction mechanism for the oxidative chlorination of methane and ethane over the Ru-oxychloride catalyst was proposed. The novel fiber glass catalyst was also tested for the dehydrochlorination of alkyl chlorides to ethylene and propylene. Very high selectivities (up to 94%–98%) for ethylene and propylene formation as well as high stability were demonstrated.

关键词： oxychlorination methane ethane light olefins ruthenium catalyst

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FeNi/Al-Ce-O催化剂上的乙烷干重整——组成诱导的金属-载体强相互作用 Article

张涛, 刘志成, 叶迎春, 王毓, 杨贺勤, 高焕新, 杨为民

《工程（英文）》 2022年第18卷第11期页码 173-185 doi: 10.1016/j.eng.2021.11.027

摘要：

在页岩气革命的背景下，乙烷干重整因在化学原料生产和碳减排方面的潜力而备受关注。本研究通过X射线光电子能谱、H₂程序升温还原和能量散射X射线谱等手段，揭示了一种组成诱导的金属-载体强相互作用。氧化铈中Al的引入增强了金属与载体之间的相互作用，显著影响了Al-Ce-O载体表面FeNi活性组分的分散度，从而提升了FeNi/Al-Ce-O催化剂的乙烷干重整反应性能。随着载体中Al含量的增加，负载FeNi催化剂的乙烷和二氧化碳的转化率与转换频率（TOF）以及一氧化碳选择性和产率都呈现先增大后减小的趋势，与载体的理论有效表面积（TESA）的变化趋势相同。其中，Al含量为50%的FeNi/Ce-Al_0.5催化剂在873 K下具有最好的乙烷干重整反应性能。结合原位傅里叶变换红外光谱（FTIR）分析观察到，Al的引入不仅增加了表面Ce³⁺和氧空位的含量，同时也促进了表面活性组分的分散，提升了负载FeNi催化剂的乙烷干重整性能。

关键词：乙烷干重整金属-载体强相互作用二氧化碳氧化铈氧空位反应机理