FUEL PROCESSING TECHNOLOGY
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2020
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IF 4.982
Muhammad Masood Khan,Lijun Jin,Muhammad Mahmood Khan,Yang Li,Hammad Saulat,Yun Zhang,Muhammad Sarfraz,Jialong Zhu,Haoquan Hu
The composite catalysts AC-Ni/MgO-Al 2 O 3 were prepared by the co-precipitation method with activated carbon (AC) and [Ni,Mg,Al]-hydrotalcite as the precursors, and characterized by XRD , TG-DTG, N 2 adsorption, H 2 -TPR and SEM, respectively. The resultant catalysts were examined for CO 2 reforming of methane. The results showed that the introduction of AC into Ni/MgO-Al 2 O 3 catalyst improved the textural properties, especially the surface area and pore volume of mesopores , and decreased the size of metal Ni. Compared with Ni/MgO-Al 2 O 3 , the composite AC-Ni/MgO-Al 2 O 3 exhibited higher catalytic activity , stability and H 2 /CO ratio. But the AC content obviously influenced the catalytic performances. High AC loading resulted in the decline of catalytic activity owing to lower surface area and fewer active Ni content in the catalyst. 10AC-Ni/MgO-Al 2 O 3 with 10% AC displayed the best catalytic activity and stability compared with Ni/MgO-Al 2 O 3 . About 86.2% conversion of CH 4 , 91.3% conversion of CO 2 and above 0.95 ratio of H 2 /CO were achieved over 10AC-Ni/MgO-Al 2 O 3 sample for the reaction time of 5430 min. This work provides a route to improve catalytic performances of Ni-based catalysts in CO 2 reforming of methane.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2023
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IF 7.7
Feng Shi,Hongyuan Wang,Yifei Chen,Yanling Lu,Defa Hou,Can Liu,Yi Lu,Xu Lin,Xiaoqin Yang,Zhifeng Zheng,Yunwu Zheng
To develop an efficient and feasible catalyst for converting inedible vegetable oil to green biodiesel via a one-step decarboxylation process, a series of Ni-based MgO-Al 2 O 3 catalysts with different active Ni species were fabricated by adjusting the various Ni loading amounts (2.5–20%) and applied to the catalytic deoxygenation of OA to generate green biodiesel. Additionally, the structure-property relationship, deactivation mechanism and regeneration performance were also evaluated via various characterization technologies (XRD, BET, NH 3 -TPD, H 2 -TPR, XPS, SEM-EDX, HRTEM, TGA, Raman as well as GC/MS and UV-fluorescence spectra). The experimental results indicated that Ni introduction obviously enhanced the conversion ratio. Ni (10%)/MgO-Al 2 O 3 catalysts exhibited excellent catalytic performance with the highest HCs (95.12%), olefin content (57.37%) and green biodiesel content (75.90%) due to mild Brønsted-rich acidity sites, lower reduction temperature, higher active metallic Ni species content, suitable oxygen vacancy content and favorable texture properties via the decarbonylation reaction pathway. Furthermore, lower Ni loading was beneficial to gasoline and bioaviation fuel generation due to higher Brønsted-rich acidity sites and total acid amount, which boosted C-C scission by cracking reaction, and higher Ni content facilitated biodiesel formation. Additionally, Ni (10%)/MgO-Al 2 O 3 catalysts showed excellent reusability and regeneration due to Ni active species, but these advantages were slightly decreased (HCs: from 95.12% to 61.63%; biodiesel: from 75.90% to 57.52%) due to coke deposition and metal active species leaching and oxidation .
研究领域:
化学工程
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
FUEL
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2023
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IF 7.4
Xiaoqian Feng,Yilin Zhao,Shenghua Liu,Kun Wang,Baoshan Liu,Qijian Zhang,Huan Wang,Yonghua Zhao,Jing Liu,Peng Zhang,Lian Gao
Dry reforming of methane (DRM) suffers catalysts deactivation due to severe coking. Ni/MgO-Al 2 O 3 is a promising system for DRM catalysts with high coking resistance, as the addition of MgO in Ni/Al 2 O 3 catalysts can improve the alkalinity of the support and enhance the metal-support interaction. However, so far the activity and stability of Ni/MgO-Al 2 O 3 is still unsatisfactory while the role of Mg addition remains unclear. In this paper, a series Ni 0.5 /xMgO-Al 2 O 3 catalysts with flower-like hollow sphere morphology and high surface area were synthesized via a facile hydrothermal method. Appropriate Mg addition promotes the formation of NiAl 2 O 4 while more Mg addition leads to the formation of Ni x Mg y O. Both cases can enhance the MSI of the catalysts without changing the morphology of the catalyst. More Mg addition also leads to stronger CO 2 adsorption via improving the alkalinity. Nevertheless, overdose of Mg results in weaker MSI and the blockage of Ni active sites. Ni 0.5 /0.5MgO-Al 2 O 3 with moderate Mg addition shows excellent activity (CH 4 ∼ 75 %, CO 2 ∼ 85 %) and stability (>100 h) at a high GHSV = 144000 ml/g cat ·h −1 and 800 °C with nearly no coking formation (<0.8 wt%). This work helps reveal the role of MgO addition in Ni/Al 2 O 3 systems and gives new insights into the design of DRM catalysts with high activity and stability.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2025
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IF 3.9
Rui Xing,Yanan Jiang,Jia Li,Pengxiang Liu,Yuan Liu,Cuijuan Zhang
Despite significant advances in catalytic activity for CO2 methanation, the catalyst stability has received less attention, limiting its application. This work prepared Ni-supported on MgO-Al2O3 with varying Mg/Al ratio (x) and studied their deactivation mechanism. The deactivation was accelerated by a stability test at 600 °C for 200 h. The activity comparison before and after the stability test reveals that the sample with x = 0.4 shows the best stability without obvious activity decline. While the sample with x = 0.3 is deactivated due to Ni sintering, samples with x = 0.5 and 0.6 are deactivated by the oxidation of Ni, which easily forms a solid solution with excess MgO but is difficult to reduce. That assertion is supported by various characterizations. Such an oxidative deactivation is first-time reported for Ni-based catalysts for CO2 methanation, which could shed light on their rational design and industrial application.
✓ 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）