INDUSTRIAL CROPS AND PRODUCTS
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2024
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IF 5.6
Xiaoran Li,Kehui Cen,Jinjin Li,Chu Wang,Dongxia Jia,Dengyu Chen
In this study, cellulose and lignin were subjected to co-pyrolysis for the production of syngas. For the pyrolysis experiments, three influencing factors were selected using a response surface method: pyrolysis temperature (400–800 °C), residence time (5–30 min), and lignin mass percentage (0–100 wt%). At a pyrolysis temperature of 477.4 °C, a residence time of 30 min, and a lignin mass percentage of 50 wt%, the actual syngas yield was 77.2 % higher than the theoretical value for the co-pyrolysis. In addition, the hydrogen volume fraction was improved by up to 24.87 % because of the interaction between cellulose and lignin during their co-pyrolysis (pyrolysis temperature of 800 °C, residence time of 17.5 min, lignin mass percentage of 80.65 wt%). Finally, the hydrogen formation process was simulated, using reactive force field molecular dynamics. The results showed that hydrogen molecules began to appear at a simulation time of 0.479 ns and then gradually increased in number with progressing simulation time. In addition, the hydrogen generation pathways were obtained by this simulation method. This study provides a data foundation for optimizing syngas and hydrogen production from biomass.
研究领域:
能源与燃料
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化学工程
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生物质能
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2024
·
IF 10.5
Q. Chen,I.M. De Cachinho Cordeiro,W. Yang,A.C.Y. Yuen,T.B.Y. Chen,W. Wang,W. Yang,G.H. Yeoh,R.K.K. Yuen
Graphdiyne (GDY) is an emerging two-dimensional carbon allotrope comprising unique sp 1 and sp 2 hybridisation, which has attracted extensive investigation into various applications, especially as battery component materials owing to its excellent electromechanical properties. However, GDY's thermal stability and oxidation behaviour have yet to be evaluated, which is crucial to safety in high-energy applications. The present study characterised the thermophysical properties of GDY via reactive molecular dynamics (MD-ReaxFF) and experimental measurement. The oxidation kinetics and decomposition behaviour were elucidated and benchmarked with graphene (GP) and graphyne (GY) to investigate the correlation between thermal stability and morphology of carbon nanomaterials. The simulation results revealed the initial oxidation mechanism of GDY sheets, where the cleavage of C–C bonds was observed at the acetylenic chain and could be identified as the weak spots of the structural stability. As for oxidation kinetics, GDY's experimental and numerical activation energy was found to be 173.1 and 133 kJ/mol, which is lower than 220.8 kJ/mol of GP. The current work pioneer investigated the thermal stability of GDY using both experimental and numerical approaches. Meanwhile, different oxidation mechanisms between GP and GDY were distinguished and demonstrated in detail.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2024
·
IF 5.2
Yuchuan Feng,Penghui Wang,Nana Wang,Xin Guo,Suxia Ma
Reactive force field molecular dynamics (ReaxFF MD) simulation and experiments were employed to deeply reveal the sintering mechanism of Fe2O3 particles during iron-based chemical looping combustion. The sintering process of Fe2O3 particles was simulated at different temperatures (973–1273 K). The results showed that the temperature increase has limited effect on the structure of Fe2O3 particles and slightly increases the atomic irregularity. The sintering process of Fe2O3 particles can be divided into three stages: the proximity phase, rapid formation, and slow growth of the sintering neck. The temperature increase significantly promotes the sintering process of Fe2O3 particles. The mean-square displacement and Arrhenius equations were used to study the atomic diffusion properties of Fe2O3 particles. The diffusion activation energy of surface atoms is lower than that of inner atoms, implying that the surface atoms have stronger diffusion ability. With the increase of temperature, more Fe atoms diffuse toward the interface of Fe2O3 particles. Increasing the temperature can accelerate the diffusion and enrichment of surface atoms, especially Fe, toward the sintering neck region, resulting in more serious sintering of Fe2O3 particles. ReaxFF MD simulation is in good agreement with the experimental results. Inhibiting the atomic diffusion is the key to improving the antisintering ability of Fe2O3 oxygen carriers.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Junjie Zhou,Shawei Tang,Jin Hu
Utilizing the oxide layer of carbon steel as an anti-corrosion protective layer is an environmentally friendly and cost-effective strategy. In this paper, a novel pressure swing oxidation (PSO) method was used to fabricate an oxide layer on the surface of Q235B, and the limiting effect of PSO on oxidation was presented using a reactive force field (ReaxFF). The surface characteristics and corrosion resistance of the oxide layers formed at varying temperature, as well as the different stage of PSO were investigated, and the formation mechanism of the oxide layer was discussed in detail. It can be found that the PSO process intensively affects the thickness, morphology and surface roughness along with phase composition of the oxide layers, which further influences the corrosion resistance. After the oxidation treatment, the corrosion current density of the treated sample was 3.31 × 10 −7 A·cm −2 which was reduced by about one order of magnitude in comparison with untreated Q235B. At the same time, an ultra-long passivation zone appeared in the corresponding polarization curve. Moreover, the impedance modulus at 0.01 Hz reached 1.29 × 10 6 Ω·cm 2 .
研究领域:
材料科学
·
腐蚀工程
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表面工程
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冶金学
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电化学
✓ 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）