FUEL PROCESSING TECHNOLOGY
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2021
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IF 7.033
Yilun Sun,Meng Huang,Jingpeng Li,Zhiyuan Wang,Jianxin Zhou
The coke in the coils has a serious impact on the long-term and stable operation of the ethylene plant . Inhibiting coking of the cracking furnace is an important issue. In this paper, the Cr/CeO 2 coatings were prepared on the surface of 310S stainless steel by high-velocity oxygen-fuel (HVOF) spraying. The anti-coking performances of the bare 310S specimen and the Cr/CeO 2 coatings were tested by using the pyrolysis of naphtha . The results show that the coating with the thickness of 10–15 μm and a very small number of pores was built up by the obviously deformed splats and the coating/substrate interface is jagged bond. The white area on the surface of Cr/CeO 2 coatings mainly includes CeO 2 . However, the gray area is made of Cr or Cr 2 O 3 . Compared with the bare 310S specimen, the coking inhibition rates of coatings are 48.7%, 58.9%, 76.1% and 88.9% when the ratio of Cr and CeO 2 powder is 19:1, 9:1, 4:1 and 3:2, respectively. With increasing the relative ratio of CeO 2 , more white areas without coke are exposed. The CeO 2 surface can not only inhibit catalytic coking, but also promote the reaction of water vapor and coke.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2023
·Vol. 58
·期 41
·16033-16045
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IF 4.5
Tian Yuhao,Li Ting,Cai Weijie
Recently, bio-ethanol reforming with CO 2 (EDR) has been considered as one of the environment-friendly processes to diminish the emission of greenhouse gas, along with increasing the production of value-added syngas. However, designing high-performance catalysts is still a great challenge. In this work, MOF-derived CoMO x (M:Ce,Zr,Zn) catalysts were applied in EDR reaction for the first time to explore the influence of support types on catalytic performance. Characterization of the investigated catalysts by XPS, XRD, H 2 -TPR, Raman, TEM and BET depicted the difference in cobalt dispersion, specific surface area as well as Co-support interaction. Indeed, H 2 -TPR and XPS results revealed stronger Co-Ce interaction and the smaller particle size of Co 3 O 4 in Co-CeO 2 catalyst which contributed to higher activity. Indeed, 100% of ethanol conversion was obtained at 550 °C and the formed H 2 /CO ratio (1.18) was suitable for the downstream Fischer–Tropsch process. Meanwhile, no remarkable decline of ethanol conversion and product distributions occurred after 40 h stability tests. The findings implied that EDR process might be suitable to consume greenhouse gas and reduce carbon footprint. Characterization results of the used catalysts indicated that Co-CeO 2 catalyst presented an outstanding anti-aggregation and anti-coking property. Herein, the effect of support type in this work might provide guidance for the design of high-performance catalysts for other heterogeneous reactions operated at high temperature. Graphical abstract
研究领域:
化学工程
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催化
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环境科学
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材料科学
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DOI
高影响因子
ACS Catalysis
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2020
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IF 12.35
Bangxin Li,Shuai He,Jibiao Li,Xiangling Yue,John T.S. Irvine,Deti Xie,Jiupai Ni,Chengsheng Ni
Employment of identical oxides for the cathode and anode in a symmetrical solid oxide fuel cell (SSOFC) is beneficial for decreasing the fabrication costs of a robust cell. Ce doping on the A site of SrFeO3 increased the structural stability in a reducing atmosphere, but ceria was found to exsolve from the perovskite during the cooling process in the air if the doping level reached 20 atom %. The additional doping of 5 atom % Ru in Sr0.8Ce0.2FeO3 on the Fe site could prevent the ceria segregation in air and induce the surface decomposition under fuel conditions for the formation of nanoscale SrO, CeO2, and Ru0. The SSOFC with Ce/Ru codoped SrFeO3 on a Sr- and Mg-doped LaGaO3 electrolyte showed a small Rp value (0.12 Ω cm2) when H2 and ambient air were used as fuel and oxidant, respectively. The peak power densities of 846 and 310 mW cm–2 were achieved at 800 °C using H2 and C3H8 as fuel, respectively. The excellent coke resistance of the anode could be related to the simultaneous in situ exsolution of CeO2, SrO, and Ru0 nanoparticles.
研究领域:
材料科学
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电化学
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能源材料
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燃料电池
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DOI
高影响因子
FUEL
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2023
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IF 7.4
Wei Zhang,Fusheng Yin,Zhenhui Cheng,Suping Peng,Chunwen Sun
To achieve the commercial application of solid oxide fuel cells (SOFCs), the performance degradation of the cell caused by carbon deposition needs to be well addressed. Here we report a new anode with nanostructured heterogeneous interfaces by integrating 0.38 wt% Sn and 0.19 wt% MgO into Ni SDC for hydrocarbon-fueled SOFCs. The cell with 0.38Sn–0.19MgO Ni SDC anode exhibits a peak power density of 374 mW cm −2 and excellent long-term stability for 100 h with a power attenuation about 13.5% in humidified methane at 700 °C, which is attributed to the decreased rate of carbon deposition by promoting the formation of C O bonds instead of C C bonds, increasing the activation barrier for methane cracking and preventing the formation of nickel carbides by the confinement effect of heterogeneous catalysts, and the enhanced rate of carbon removal is attributed to excellent hydrophilicity and adsorption of CO 2 , as revealed by combined density function theory (DFT) calculations and experimental characterizations. This finding offers potential for the application of hydrocarbon-fueled SOFCs and provides a guide for designing coking-tolerant anodes.
研究领域:
材料科学
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能源工程
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化学工程
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电化学
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产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2021
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IF 5.541
Fangqi Wang,Fengwen Yu,Yi Wei,Ao Li,Shenzheng Xu,Xianghong Lu
Oleaginous biomass conversion to liquid hydrocarbon biofuels has emerged as an effective solution to the energy crisis and environmental problems. In this process, the removal of oxygenated compounds will directly affect the effectiveness of subsequent biofuel applications. Herein, deoxygenation of oleic acid by catalytic cracking was conducted using five various elements (La, Ni, P, Zr and Ce) modified Al-MCM-41. The related characterizations were carried out for these catalysts, including N 2 physisorption, XRD, XPS, pyridine-FTIR and NH 3 -TPD techniques. The results showed the mesoporous structure of Al-MCM-41 was maintained after different modifications, and these catalysts greatly improved the hydrocarbons content and physiochemical properties of biofuels. The modified catalysts tended to facilitate the decarbonylation pathway and showed high selectivity to alkane and aromatic hydrocarbons. Besides, La/Al-MCM-41 presented excellent anti-coking activity. Ni/Al-MCM-41 showed both high dehydrogenation and deoxygenation activities. The Zr modification and Ce modification had a promotion effect in the deoxidizing activity of the catalyst, owing to the formation of oxophilic metal oxides. Noteworthily, P/Al-MCM-41 displayed the best deoxidizing performance due to its high Brönsted acidity, which caused the highest hydrocarbons content (82.30 %) and the lowest fatty acids content (around 0 %) of the biofuel. Moreover, the resulting biofuel had not only low oxygen content (3.88 wt.%) and acid value (5.47 mgKOH g −1 ) but also a high calorific value (44.50 MJ kg −1 ), which could be processed into green diesel. Hence, the catalytic cracking of fatty acid over P/Al-MCM-41 has excellent potential to produce high-quality renewable fuels.
研究领域:
化学工程
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可再生能源
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催化
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生物化学
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DOI
高影响因子