CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Xing Zhang,Jingfeng Wu,Tian Li,Chengzhi Zhang,Lingjun Zhu,Shurong Wang
Hydrodeoxygenation (HDO) of lignin-derived bio-oil offers a promising route for the production of advanced biofuels. However, the conventional HDO of lignin-derived bio-oil faces serious problems, such as low hydrocarbon yield and easy deactivation of catalysts. Herein, a novel reaction system consisting of a highly stable bifunctional catalyst (i.e., Ni−WO x /NiAl 2 O 4 ) and a dodecane solvent was developed for the HDO of lignin-derived phenolics. The Ni 0 species, derived from NiWO 4 precursors on the NiAl 2 O 4 , were of small crystallite size and high dispersion, together with the strong oxophilicity of W, thereby exhibiting high activity. The use of a highly stable NiAl 2 O 4 spinel support and the replacement of common solid acid with more stable WO x for the cleavage of C O bond accounted for excellent stability. The optimized 10Ni−15WO x /NiAl 2 O 4 exhibited a high guaiacol conversion of 97.8% with a high cycloalkane yield of 83.8% under the optimum conditions (250 °C, 5 MPa H 2 , and 4 h). Cycloalkanes with a high yield over 90% were also obtained by the HDO of other complex lignin-derived compounds. More importantly, the catalyst always retained its initial activity for the HDO of guaiacol in five runs, with negligible coke formation. Subsequently, the HDO behavior of the bio-oil obtained from walnut shell pyrolysis was also studied. The relative content of cycloalkanes in the products reached 44.3% after the reaction. This study highlights the prospect of a highly stable catalyst consisting of hydrogenation metal and oxophilic promoter, and dodecane solvent to enable efficient production of cycloalkanes from the HDO of lignin-derived phenolics.
研究领域:
能源化学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Zheng Li,Jiehao Xie,Zipin Peng,Zhuo Ma,Yihui Li,Xingkun Chen,Yuan Tan,Wenshao Yang,Yunjie Ding
4-Chlorophenol (4-CP) is a pervasive environmental pollutant commonly found in wastewater and groundwater, posing great risks to both human health and the ecosystem. Catalytic hydrodechlorination (HDC) of 4-CP by utilizing hydrogen (H 2 ) as a reductant has emerged to be an efficient and sustainable way to treat pollutant water. This study focuses on the development of an efficient and stable Pd-based catalyst for the catalytic HDC of 4-CP. By incorporating an appropriate amount of Ni into Al 2 O 3 support, a NiAl 2 O 4 (NA) spinel was synthesized, enhancing the interaction between Pd and the support, leading to precise control over Pd species and oxygen vacancies. The tailored properties of the Pd/NA-1 catalyst result from meticulous adjustment of the Pd 2+ /Pd 0 ratio and oxygen vacancies, which promotes electron transfer from Pd to Ni within the NiAl 2 O 4 spinel. In comparison to the Pd/Al 2 O 3 catalyst, the Pd/NA-1 catalyst exhibits exceptional stability, with continuous operation for over 120 h without deactivation. Comprehensive characterization analyses indicate that the Pd/NA-1 catalyst effectively prevented the aggregation of Pd nanoparticles, maintaining the Pd 2+ /Pd 0 ratio at 1, which is crucial for its superior stability. This work provides valuable insights into the development of Pd-based catalysts for HDC reactions, highlighting the potential use of Pd/NA-1 catalysts in treating hazardous pollutants like 4-CP in waste systems.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
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2019
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IF 12.221
Didi Li,Yi Li,Xiaohui Liu,Yong Guo,Chih-Wen Pao,Jeng-Lung Chen,Yongfeng Hu,Yanqin Wang
The production of hydrogen from the aqueous-phase reforming (APR) of oxygenated hydrocarbons is promising. Herein, the performances of Pt loaded on NiAl2O4 spinel and γ-Al2O3 were investigated in the APR of methanol. The conversion of methanol and the yield of hydrogen over Pt/NiAl2O4 reached 99.9% and 95.7%, respectively. In comparison with Pt/γ-Al2O3 catalyst (26.5% and 23.3%, respectively), these values were enhanced by 4-fold. More importantly, Pt/NiAl2O4 had high stability with only 10% loss of its initial conversion after 600 h on stream. In situ diffuse reflectance infrared Fourier transform spectra (DRIFTS) of the APR of methanol revealed that the reaction underwent the dehydrogenation of methanol and the sequential water–gas shift (WGS) reaction. These two reactions were then investigated independently, in which Pt/NiAl2O4 showed more efficient performance than Pt/γ-Al2O3. Intensive characterization methods revealed that the chemical state of Pt played a pivotal role in the dehydrogenation of methanol to generate the adsorbed CO intermediate. For Pt/NiAl2O4 catalyst, the reduction of PtOx to metallic state Pt was easier because of the presence of the oxygen vacancy, leading to the higher catalytic performance in the dehydrogenation of methanol. Further studies with in situ DRIFTS-MS of WGS demonstrated a redox mechanism over Pt/NiAl2O4 catalyst, which was different from the associative route that occurred over Pt/γ-Al2O3 and made the WGS reaction faster. The addition of Ni (NiAl2O4 spinel) creates oxygen vacancies, giving WGS which underwent a redox route. This work presents the deep understanding into the pathway and mechanism in the APR of methanol and is expected to have important implications for the future development of APR catalysts.
研究领域:
催化化学
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材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2021
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IF 5.816
Zhoufeng Bian,Wenqi Zhong,Yang Yu,Zhigang Wang,Bo Jiang,Sibudjing Kawi
Catalysts of Ni supported on home-made mesoporous alumina (Ni/M-Al 2 O 3 ) were prepared via facile incipient impregnation method and calcined under different temperature (500–800 °C). Compared with catalysts of Ni supported on commercial alumina, they showed much higher conversion and lower carbon deposition in methane dry reforming (DRM). Among the catalysts, Ni/M-Al 2 O 3 -700 exhibited the highest DRM activity, with 77.6% CH 4 conversion and 85.4% CO 2 conversion at 700 °C. TPR revealed that almost all the Ni was in the form of NiAl 2 O 4 spinel after calcination at 700 °C. Due to the strong metal-support interaction of NiAl 2 O 4 structure, the Ni crystal size of Ni/M-Al 2 O 3 -700 after reduction was around 5 nm. TGA and TEM results showed its carbon deposition after 20 h DRM test was only 3.8% and mainly in the form of amorphous carbon . This work indicates that the formation of NiAl 2 O 4 spinel is beneficial to activity and stability towards DRM reaction and controlling calcination temperature is crucial.
研究领域:
催化化学
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材料科学
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能源化学
✓ 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）