ChemCatChem
·
2023
·Vol. 15
·期 8
·e202300136
·
IF 4.5
Ruifan Tan,Ping Wang,Luyao Guo,Zupeng Chen,Ronghe Lin,Xiaoling Mou,Yunjie Ding
Graphical The shape of zirconia hosts can tune the nature of active nickel species and the number of lattice oxygen species, which strongly influences the reaction and coking rates in the dry reforming of methane. The shape of the carriers has a profound impact on the catalytic performance of metal-supported catalysts. Herein, ZrO 2 of different shapes (nanorods-like, spherical or irregular nanoparticles, demoted as RZ, SPZ, and IPZ, respectively) are adopted to disperse Ni species to assess the shape effects on the catalytic performance in dry reforming of methane. To this end, the fresh and spent catalysts are thoroughly characterized by multiple techniques including N 2 sorption, powder X-ray diffraction, temperature-programmed reduction with H 2 , thermogravimetric analyses, transmission electron microscopy, Raman and X-ray photoelectron spectroscopies. It is revealed that the reducibility of NiO species follows the orders of Ni/RZ
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2021
·
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
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Jun Zhao,Haibin Zuo,Guangwei Wang,Jingsong Wang,Qingguo Xue
To effectively utilize low-rank coal and biomass in the coking process, through the dissolution method, hypercoal (HPC) was produced, and its performance as an additional component in the coking process was also investigated. The cold strength of coke was tested using an I-type tumble tester and a universal testing machine; the carbon structure of the HPCs was examined via thermogravimetry (TG), X-ray diffraction (XRD), and Fourier transform infrared spectrometry (FT-IR) analyses. The results revealed that the thermoplastic properties of HPCs and the coke cold strength increased compared to raw coal. There is a positive linear relationship between the cold strength of coke and the order degree of the HPCs. As the biomass amount increased, the order degree of the HPCs greatly decreased, resulting in a decrease in the coke cold strength. When the amount of biomass was 20%, the caking index (G), drum strength, and compressive strength achieved maximum values of 95.21%, 83%, and 7.13 MPa, respectively. In addition, a caking mechanism of the HPCs is proposed.
研究领域:
燃料化学
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煤化工
·
材料科学
·
能源工程
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工业化学
·
资源利用
✓ 已验证
DOI
高影响因子
FUEL
·
2020
·
IF 5.578
Shun Li,Yongsheng Guo,Wenjun Fang,Guijin He
A sulfur-rich segmental hyperbranched polymer , SHPGMA, is developed to inhibit the catalytic coking during the thermal cracking of hydrocarbon fuels. In this work, the SHPGMA with a narrow molecular weight range is prepared via the principle of reversible addition-fragmentation chain transfer polymerization. The decomposition of n- dodecyl in SHPGMA takes place firstly at about 170 °C, and the dissociation of the skeleton of SHPGMA occurred in the range from 290 to 500 °C, which indicates a wide onset temperature range. The cracking reactions of n- tridecane with or without SHPGMA under different conditions show that SHPGMA can inhibit the catalytic cracking of n- tridecane, which results in significant reduction of the catalytic coke, conversion and heat sink. With the function of SHPGMA, the filamentous coke deposited in the pipeline is significantly reduced, and the generated coke become incompact and small. The amount of coke per cracked n- tridecane decreases from 38.42 to 27.03 μg/g with the addition of 0.03 wt% SHPGMA-3. These results confirm the potential application of SHPGMA as the coke inhibitor to endothermic hydrocarbon fuels.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2025
·
IF 6.2
Kaiwen Yun,Xixi Lian,Shuxiao Wang,Rui Shan,Haoran Yuan,Yong Chen
The development of low-cost, renewable catalysts for catalyzing the pyrolysis of waste plastics to enable selective upgrading and recycling remains a major challenge. This study reports a novel biochar-loaded calcium-based catalyst that demonstrates excellent olefin selectivity and catalytic efficiency in situ pyrolysis of polypropylene, outperforming traditional catalysts in catalytic performance. The reaction was performed using an in-house developed carbon-based calcium catalyst, which was characterized and examined using a variety of analytical test methods. The effects of catalyst calcium metal loading, feedstock/catalyst ratio and reaction temperature on pyrolysis oil yield and olefin content were investigated. The results showed that olefins and cycloalkanes were the main components of pyrolysis oil in the catalytic pyrolysis experiments, with carbon number distribution between C 13 and C 25 . Under optimal conditions (480 °C, 25% Ca loading, feedstock/catalyst ratio of 1:0.2), a maximum pyrolysis oil yield of 93.75% (0.91 g/g pp ) was achieved, with an olefin content of 58.87% (0.55 g/g pp ). The high dispersion of Ca 2+ species on the porous biochar support was found to synergistically promote C–C bond cleavage while suppressing coke formation via pore confinement and radical stabilization mechanisms. This work offers a promising strategy for the sustainable production of high-quality oils from plastic waste.
研究领域:
化学工程
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环境科学
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材料科学
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催化
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聚合物回收
✓ 已验证
产品关联
DOI
高影响因子
Sustainable Energy & Fuels
·
2020
·Vol. 4
·期 6
·2768-2774
·
IF 5.503
Qinghai Yang,Congquan Zhou,Jihong Ni,Xiaofei Guan
We present a liquid catalytic system comprising a liquid Ni–Bi alloy and a molten K2CO3 salt, which completely resolves the coking and sintering issues for dry reforming. The conversions of CH4 and CO2 reach 60% and 70%, respectively, in a 30 cm bubble column comprising 15 cm Ni0.27Bi0.73 and 15 cm K2CO3 at 1050 °C. The CO selectivity is near 100% throughout the temperature range of 950–1050 °C. A 120 hour stability test at 1000 °C shows no performance degradation, suggesting a stable and effective dry reforming process for syngas production. The catalytic performance and durability demonstrated highlight the potential of dry reforming for commercial applications.
研究领域:
化学工程
·
催化
·
能源转换
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Siwei Liu,Xiangqian Wei,Weitao Sun,Chenguang Wang,Wenzhi Li,Longlong Ma,Qiying Liu
Considering process efficiency, flow and coking are important aspects in biomass and its derivatives for catalytic conversion to value-added products. However, these investigations are scarcely involved due to the very complex reaction environment and coupling mass transfer and coking process. To better understanding the coking process in glucose catalytic conversion to levulinic acid (LA), a particle-scale model based on the lattice Boltzmann model (LBM) was proposed. In this model, a coking model based on te volume of pixels scheme was developed to simulate the coking deactivation process, and a zeolite permeability model based on the gray LBM scheme was developed for fluid permeation inside shaped zeolite. The model was validated by both analytical and experimental data. The effects of temperature, particle porosity, and coking on catalyst deactivation, product yield, and selectivity were investigated. The numerical results indicated that the deactivation time of shaped zeolite peaked at the particle porosity of 0.20 and increased as the operating temperature decreased. Glucose conversion, LA yield, and humins yield increased with the increase of particle porosity and operating temperature. The opposite trend of the intermediate 5-hydroxymethylfurfural (HMF) was found when the temperature and porosity were increased. The results also showed that the LA selectivity and the yield ratio of LA to humins peaked at a porosity of 0.45 and a reaction temperature of 180 °C.
研究领域:
化学工程
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催化
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计算流体力学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2023
·Vol. 58
·期 41
·16033-16045
·
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
·
催化
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2020
·
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
·
电化学
·
能源材料
·
燃料电池
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
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
·
能源工程
·
化学工程
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2021
·
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
·
可再生能源
·
催化
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）