INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·
IF 4.229
Bin Li,Baohua Zhang,Qingqing Guan,Shanshuai Chen,Ping Ning
An effective Ni/CeO 2 catalyst prepared by the polyol reduction method for degrading phenol into CH 4 , H 2 and CO 2 in supercritical water (SCW) was developed. About 80% carbon gasification efficiency can be achieved at 525 °C and 60 min with 5 wt% phenol, 0.098 kg/m 3 water density and 0.5 g Ni/CeO 2 /g phenol catalyst, forming CH 4 and H 2 as the main gaseous products. Comparison study indicated that the efficiency of present Ni/CeO 2 catalyst was about 20% higher than that of a commercial catalyst, i.e., Ni/SiO 2 Al 2 O 3 from Sigma-Aldrich with 65 wt%Ni, at a reaction conditions of 500 °C and 30 min. The characterization analyses of BET, TPR, XRD , XPS and TEM indicated that there was a NiCe alloy formed in Ni/CeO 2 , which could be important to enhance the activities of the carbon gasification efficiencies and gas yields. A kinetic modelings were conducted and the results showed that the lnA and the activation energy (Ea) of gasification were 7.1 ± 0.5 and 58.1 ± 3.2 kJ/mol for the gaseous product, and were 2.6 ± 0.9 and Ea is 36.6 ± 5.6 kJ/mol for the char formation , respectively. The present Ni-based-metal Ni/CeO 2 catalyst is cheaper and has a potential application for the gasification to convert phenol into gases fuels in SCW process.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysts
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2022
·Vol. 12
·期 6
·606
·
IF 4.501
Yadong Wang,Qing Hu,Ximing Wang,Yanpeng Huang,Yuanhao Wang,Fenghuan Wang
Methane reforming with carbon dioxide (DRM) is one promising way to achieve carbon neutrality and convert methane to syngas for high-value chemical production. Catalyst development with better performance is the key to its potential large-scale industrial application due to its deactivation caused by carbon deposition and metal sintering. Hence, a Ni/CeO2catalyst (Ni/CeO2-M) with higher CO2conversion and better stability is prepared, supported on CeO2precipitated via a novel microimpinging stream reactor. A series of ex-situ or in-situ characterizations, such as CO titration measurements, two-step transient surface reaction (two-step TSR), CO2and CH4temperature-programmed surface reaction (CO2-TPSR and CH4-TPSR), X-ray absorption fine structure (XAFS), and in-situ Raman spectroscopy study, were used to investigate its structure and mechanism. In contrast to Ni supported on commercial CeO2(Ni/CeO2-C), the Ni/CeO2-M catalyst with stronger lattice oxygen mobility and higher oxygen storage capacity enhances its CO2activation ability and carbon deposition. The Ni particle size of the Ni/CeO2-M catalyst decreased, and a higher oxidation state was obtained due to the strong metal–support interaction. Besides the reaction performance improvement of the Ni/CeO2-M catalyst, the novel microimpinging stream reactor could achieve catalyst continuous production with a high preparation efficiency. This work provides a novel method for the high-performance catalyst preparation for DRM reaction and its mechanism study gives a deep insight into high-performance catalyst development via bottom-up study.Keywords:dry reforming of methane;oxygen vacancy;Ni/CeO2catalyst
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
RARE METALS
·
2017
·Vol. 37
·期 2
·148-153
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IF 1.189
Jin Hui,Wang Yi-Yong,Wang Yu-Ting,Yang Hong-Bing
Current machinery requires metallic materials to have better surface properties. Based on an orthogonal experimental design and analysis method, the CeO 2 -reinforced nickel nano-composite coatings were prepared by direct current electrodeposition in a nickel sulfate bath containing CeO 2 nanoparticles. Statistical results indicate that current density is the most significant variable in the electrodeposition processing, while temperature is the least important factor. The microstructure of Ni and Ni–CeO 2 nano-composite coatings was characterized by scanning electron microscopy (SEM) equipped with energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The microhardness of the Ni coating is enhanced by the incorporation of CeO 2 nanoparticles. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were used to characterize the corrosion behavior of Ni and Ni–CeO 2 coatings. These studies show that Ni–CeO 2 coating has better corrosion resistance compared to Ni coating.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
·
IF 9.136
Zongze Lv,Jiaqi Ruan,Weifeng Tu,Xun Hu,Donglin He,Xin Huang,Changlei Qin
Integrated carbon capture and utilization by methanation (ICCU-methanation) is an emerging concept in reducing CO 2 emissions and storing H 2 simultaneously. One key of the technology is the development of dual functional materials (DFMs) that can efficiently capture CO 2 and then catalyze it. Herein, we propose the construction of DFM using Li 4 SiO 4 with superior CO 2 adsorption/desorption features as sorbent and catalyst carrier, CeO 2 as catalyst promoter and isolator, and Ni as catalytic metal, and comprehensively evaluate its characteristics and performance in ICCU-methanation. Results show that the DFM developed possess a high and stable CO 2 capacity of 5.4 mmol·g DFM -1 , 96 % CO 2 conversion and 96 % CH 4 selectivity under both the ideal CO 2 capturing atmosphere and the realistic flue gas containing 10 vol% steam and 8 vol% O 2 . Moreover, rapid CO 2 dissociation from the DFM is observed at a temperature lower to 560 °C due to the reaction of H* dissociated by catalyst with carbonate to form formate, which further decomposes to release CO.
研究领域:
能源化学
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环境科学
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2021
·
IF 5.062
Rui Tang,Niamat Ullah,Yajun Hui,Xin Li,Zhenhua Li
Carbon dioxide hydrogenation for value-added chemicals has been regarded as a promising way for CO 2 utilization. This paper describes the preparation of Ni/CeO 2 catalysts derived from Ce-MOF precursor by impregnation or one-pot method and their application in carbon dioxide methanation. Various techniques were employed to characterize the prepared catalysts, including N 2 adsorption–desorption, X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (SEM), H 2 -temperature programmed reduction (H 2 -TPR), H 2 -temperature programmed desorption (H 2 -TPD) and CO 2 -temperature programmed desorption (CO 2 -TPD). The results showed that compared with commercial CeO 2 and CeO 2 prepared by precipitation, CeO 2 derived from Ce-MOF exhibited more oxygen vacancies and lower temperature reducibility, making it more beneficial for the adsorption and activation of CO 2 . Consequently, nickel supported on rod-shaped CeO 2 derived from Ce-MOF exhibited higher CO 2 conversion and methane selectivity at low temperatures. Furthermore, the Ni/CeO 2 −M-1 catalysts prepared by one-pot method showed superior activity since nickel could be partially incorporated into ceria lattice, leading to the formation of Ce 1-x Ni x O 2-y solid solutions and oxygen vacancies. The effect of nickel loading on the properties of the catalysts by one-pot method was also investigated, and the optimum Ni loading was 15 wt.% owing to the maximum number of oxygen vacancies being reached.
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
·
IF 24.319
Zhihe Zhang,Zihang Yu,Kai Feng,Binhang Yan
CO 2 methanation is gaining renewed attention due to the emerging application needs such as the power-to-gas concept and long-term space exploration missions. Maximizing the amounts of interfacial sites generally regarded as the efficient active sites is considered to be one of the most direct means to enhance catalytic activity but few breakthroughs have been made. Here, Eu 3+ is introduced to Ni/CeO 2 to promote the Ni-CeO 2 interaction, resulting in a remarkable low-temperature CO 2 methanation activity. Structural characterization indicates that the Ni/CeEu(9:1) catalyst achieves higher Ni dispersion compared to Ni/CeO 2 , which consequently generates more interfacial sites. More interfacial sites enhance the proportions of bidentate carbonates closer to interfacial sites as a faster hydrogenated species during the catalytic process, leading to enhanced low-temperature CO 2 methanation activity over the Ni/CeEu(9:1) catalyst. This work provides a chemical strategy to enhance the amounts of active sites and bring insights into the origin of enhanced catalytic performance.
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
FUEL
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2022
·
IF 8.035
Ji Zhao,Jing-Hui Lv,Xian-Yong Wei,Qian-Qian Kong,Jia-Hao Li,Yang-Yang Zhang,Zhuang Li,Li Li,Zi-Chun Fan,Zhi-Min Zong
Ni/CeO 2 -La 2 O 3 with strong acidity was prepared by in - situ carbon templating (ISCT) and subsequent reduction with H 2 . The phase composition, specific surface area, morphology, acidity, and elemental valence composition of the catalyst were characterized. The catalytic methylation (CM I ) of phenol over the catalyst in different ratios of methanol to n -hexane was investigated under N 2 atmosphere. Over the catalyst, phenol was completely converted into 2,6-xylenol at 260 °C for 3 h via the CM I of phenol to o -cresol and subsequent CM I of o -cresol.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
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2024
·
IF 9
Daxin Jiang,Min Lin,Yuhao Yan,Lulu Zhan,Rui Li,Yulong Wu
Catalytic hydrodeoxygenation (HDO) is an effective way to produce high–value products from lignin-derived phenolic compounds. In this work, three different morphologies of Ni/CeO 2 catalysts (amorphous, cubic, and rod-shaped) have been prepared through the conventional wet impregnation method. They can be used for the HDO of guaiacol to prepare cyclohexanol, an important chemical raw material. The influence of different morphologies of CeO 2 on catalytic activity was explored. The research results indicate that Ni/CeO 2 –r catalysts with rod-shaped structures exhibit excellent catalytic properties. As a result, a 100 % conversion rate and 96.9 % cyclohexanol yield were achieved on the Ni/CeO 2 –r catalyst at 240 °C. The catalytic performance of the three catalysts follows this order: Ni/CeO 2 –r (rod-shaped) > Ni/CeO 2 –c (cubic) > Ni/CeO 2 –p (amorphous). The results of Raman and XPS indicate significant differences in the surface oxygen vacancy in catalysts with different morphologies. The Ni/CeO 2 –r catalyst has the highest oxygen vacancy concentration and defect. In addition, Ni/CeO 2 –r also has the largest specific surface area (S BET ) and the highest nickel dispersion, and forms more Ni 0 because of the strong interaction of Ni species and CeO 2 support. Therefore, Ni/CeO 2 –r exhibits the most excellent catalytic performance for the hydrogenation of guaiacol than the other two catalysts. Moreover, the cycling activity test was also investigated over the Ni/CeO 2 –r catalyst. After five cycles, the conversion rate of guaiacol and the yield of cyclohexanol hardly decrease. This work provides vital ideas for the development of higher-activity, higher-stability, and low-cost catalysts for the conversion of lignin-derived phenolic compounds in the future.
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
FUEL
·
2022
·
IF 8.035
Ji Zhao,Xian-Yong Wei,Jing-Hui Lv,Qian-Qian Kong,Jia-Hao Li,Zhuang Li,Zi-Chun Fan,Li Li,Yang-Yang Zhang,Zhi-Min Zong
Ni/CeO 2 with medium-strong acidity was prepared by in - situ carbon templating (ISCT) and reduction with H 2 . Oxydibenzene (ODB) and benzyloxybenzene (BOB) were used as lignin-related model compounds (LRMCs). Over Ni/CeO 2 , ODB was completely converted into cyclohexane ( CH I ) under initial hydrogen pressure (IHP) of 2 MPa at 160 °C for 2 h and complete conversion of BOB to CH I and methylcyclohexane (MCH) was achieved under IHP of 2 MPa at 120 °C for 1.5 h. H … H transfer to the benzene rings (BRs) in the LRMCs and phenol from BOB hydrocracking results in the BR hydrogenation, while H + transfer to the oxygen atom in BOB, hydrogenated ODB, and BOB-derived cyclohexanol ( CH II ) leads to the >CH-O- bond cleavage and subsequent dehydration of the resulting protonated CH II (PCH II ) . In addition, Ni/CeO 2 exhibits an excellent reusability.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
KINETICS AND CATALYSIS
·
2018
·Vol. 58
·期 6
·800-808
·
IF 0.926
Tang Chengli,Liping Lv,Zhang Limei,Tan Luxi,Dong Lichun
Ni@CeO 2 core–shell catalysts were synthesized via a facile surfactant-assisted hydrothermal method and their catalytic performance in the dry reforming of methane (DRM) reaction was evaluated. A variety of techniques including XRD, N 2 adsorption–desorption, SEM, TEM, TPO, TGA were employed to characterize the prepared or spent catalysts. The encapsulation by the CeO 2 shell, on one side, can restrict the sintering and growth of Ni nanoparticles under harsh reaction conditions. On the other side, compared to the conventional shell material of SiO 2 , CeO 2 can provide more lattice oxygens and vacancies, which is helpful to suppress coke deposition. Consequently, the Ni@CeO 2 core–shell catalysts exhibited better catalytic activity and stability in the DRM reaction with respect to the referenced Ni@SiO 2 core–shell catalysts and Ni/CeO 2 supported catalysts.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
·
IF 20.2
Chunmin Zhang,Chunli Wang,Qingyun Shi,Xiaoli Wang,Shaolei Zhao,Long Liang,Qingshuang Wang,Limin Wang,Yong Cheng
The high hydrogen release temperature and thermodynamic stability of the coordination hydride LiAlH 4 render it unsuitable for direct application. This work intends to improve the hydrogen release properties via compositing LiAlH 4 and AlH 3 with similar initial hydrogen release temperatures and introduce efficient additive Ni/CeO 2 composite. The thermal stability of the composite system LiAlH 4 -AlH 3 is enormously reduced compared to that of LiAlH 4 . In addition, the preferential release of hydrogen from LiAlH 4 in the composite system provides additional heat for the subsequent release of hydrogen from AlH 3 , accelerating the hydrogen release process. As a result, LiAlH 4 -AlH 3 -Ni/CeO 2 composite performs enhanced hydrogen release performance with a hydrogen release capacity of 8.27 wt% hydrogen within 300 ℃ and a dehydrogenation onset temperature as low as 72.9 ℃. The enthalpy change of the first step hydrogen release reaction decreases from −11.99 kJ mol −1 (LiAlH 4 ) to −2.02 kJ mol −1 (LiAlH 4 -AlH 3 ). Theoretical calculations indicate that both atomic dehybridisation and electron redistribution expedite the breaking of the Al-H bond and the consequent release of hydrogen.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2022
·
IF 7.139
Hui Wang,Hao Zhu,Yuelan Zhang,Jianglong Pu
A series of CTAB-templated Ni/Ce catalysts were synthesized by adding CTAB during the hydrothermal synthesis of ceria to improve the pore structure of catalysts. Their catalytic performance was evaluated in the steam reforming of acetic acid and the effects of CTAB concentration on the porous structures , reducibilities , morphology, and activity of catalysts were studied. The catalysts were characterized by BET, XRD , H 2 -TPR, XPS , HRTEM , in-situ DRIFTS , DTG , FTIR , and temperature-programmed reaction to elucidate the structure-activity relationship of the catalyst. The results showed that owing to the CTAB assistance, a high surface area of ceria could be achieved, which induced a better Ni dispersion with a smaller Ni size, strengthened the interaction between Ni and CeO 2 , and promoted the reducibility of Ni, obtaining higher activity and lower methane yield than Ni/Ce. Among these prepared samples, Ni/Ce–C6 showed the highest surface area and the best catalytic performance with a hydrogen yield of up to 82.5% even at a low temperature (550 °C). Owing to the stronger Ni-ceria interaction of Ni/Ce–C6, the lattice oxygen in ceria migrates easily to the Ni surface , interacts with the reaction intermediates, and thus improves the CO 2 /CO ratio in the products. Much more CO and CO 2 and less CH 4 were observed over Ni/Ce–C6 during the temperature-programmed reaction, indicating its high activity. In-situ DRFITS characterization demonstrated that the two types of catalysts had similar reaction intermediates but various adsorption and conversion abilities toward the acetic acid. More reaction intermediates were adsorbed at low temperatures and a higher conversion was obtained over Ni/Ce–C6 owing to its better Ni dispersion. The CTAB assistance inhibited the formation of amorphous carbon but facilitated the formation of graphitic carbon at ∼637 °C which did not induce catalyst deactivation .
研究领域:
化学工程
·
催化材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）