Catalysts
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2022
·Vol. 12
·期 6
·606
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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
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
FUEL
·
2024
·
IF 6.7
Shafqat Ullah,Yongqi Pan,Qiangqiang Xue,Tianyi Huang,Yizhi Hu,Runping Ye,Yujun Wang,Guangsheng Luo
CO 2 methanation has emerged as a key strategy for its potential uses and ability to alleviate climate change by reducing CO 2 emissions. Herein, we present a controllable and continuous improved coprecipitation catalyst preparation method employing a T-junction microreactor to investigate La doped Ni-CeO 2 catalysts. A series of catalysts was systematically synthesized, with Ni/CeLa (5:5) emerging as the most promising candidate, exhibiting 76 % CO 2 conversion at 250 °C and 60.5 mmol/g cat .h space–time yield of methane. Different structural characterization techniques, including in-situ Raman, Quasi in-situ XPS, in-situ DRIFTS, and DFT calculations were employed to unravel the structure activity mechanisms contributing to the enhanced catalytic performance. The findings indicate that the introduction of La as a dopant reduces particle size, promotes Ni dispersion, and increases interfacial sites. These enriched interfacial sites contribute a pivotal role in facilitating the adsorption and hydrogenation of bicarbonate species, ultimately leading to improved methanation performance. This study not only highlights the efficiency of the La doped Ni-CeO 2 catalyst, but it also gives valuable insights for chemical strategy to improve structure activity relationships and mechanism studies for efficient CO 2 methanation performance.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
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
Molecular Catalysis
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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
FUEL
·
2024
·
IF 6.7
Bin Fu,Yuqiong Zhao,Shipeng Zhang,Ying Wang,Jun Liu,Guojie Zhang
Nickel-based catalysts frequently encounter significant challenges in achieving both high CO 2 conversion and superior CO selectivity during reverse water gas shift (RWGS) reactions. To address this issue, we developed a facile strategy to prepare highly dispersed Ni/CeO 2 catalysts by forming Ce 1−x Ni x O 2−y solid solutions. Under conditions of 300–600 °C, 0.1 MPa, and a gas hourly space velocity (GHSV) of 40,000 mL g cat −1 h −1 , the 5Ni/CeO 2 -A catalyst exhibited outstanding selectivity, approaching 100 %. The RWGS reaction rate reached 1332 μmol CO g Ni −1 s −1 and maintained stable for 50 h almost without deactivation. The formation of Ce 1−x Ni x O 2−y solid solution uniformly disperses numerous Ni species in the CeO 2 lattice, effectively inhibiting Ni aggregation. This highly dispersed Ni weakens CO adsorption and facilitates its direct desorption without excessive hydrogenation. Moreover, the catalyst remains well-dispersed state even after reduction. The formed Ce 1−x Ni x O 2−y solid solution generates abundant oxygen vacancies on the catalyst surface, enhancing H 2 dissociation. The catalyst’s pore size distribution is also modified, creating stacked pores that favor reactant diffusion and expose more active centers. In-situ DRIFTS experiments demonstrate that Ce-OH plays a pivotal role in CO 2 adsorption on the 5Ni/CeO 2 -A catalyst, while the stabilization of bicarbonate and formate intermediates by the highly dispersed Ni further promotes catalytic performance. This study introduces a novel preparation method and provides valuable insights for designing Ni-based catalysts with exceptional CO selectivity.
研究领域:
催化化学
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材料科学
✓ 已验证
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
APPLIED ENERGY
·
2023
·
IF 11.2
Xiangyu Yan,Buchu Lu,Hao Dong,Qibin Liu
Combining solar light and heat in dry reforming of methane (DRM) is a promising technology for reducing CO 2 to a valuable syngas and increasing the utilization of solar light in the solar-to-fuel process. The reaction temperature is still high and the mechanism remains unclear in DRM. Clarifying the synergistic mechanism of solar light and heat is pivotal for industrial applications. To this end, a nanoscale Ni/CeO 2 catalyst is prepared, and the synergistic effect of solar light and heat in DRM is experimentally investigated. The experimental results show that photo-thermochemistry leads to a 39.74% increase in relative conversion rate of CH 4 compared to thermochemistry, while the reaction temperature is reduced by 45 °C. The syngas production rate and the selectivity of DRM are improved by solar light. The in-situ infrared study indicates that solar light enhances the dissociation process of CH 4 and the production of HCOO ⁎ on the surface of the Ni/CeO 2 catalyst. The light response in the catalyst and microscopic enhancement of intermediate products are responsible for the increased DRM performance under photo-thermochemical conditions. These findings contribute to the understanding of the synergistic effects of solar light and heat, and guide the conversion of CO 2 into fuel with the aid of solar energy.
研究领域:
化学工程
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可再生能源
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 11
·期 9
·3241-3250
·
IF 6.119
Ming Jiang,Xiaopeng Chen,Linlin Wang,Jiezhen Liang,Xiaojie Wei
Selective hydrogenolysis of aryl ethers to produce aromatic compounds is a key strategy for lignin valorization. The use of non-noble-metal catalysts to realize the cleavage of C–O ether bonds under mild conditions has been of considerable research interest recently. We herein report the synthesis of a nitrogen-doped porous-carbon-skeleton-supported Ni–CeO2 catalyst (Ni–CeO2/CN). The synergistic effect between Ni and CeO2 species led to the Ni–CeO2/CN catalyst having a high activity and selectivity for the cleavage of C–O ether bonds at a low reaction temperature. In particular, the Ni–CeO2/CN catalyst showed excellent effectiveness in the hydrogenolysis of benzyl phenyl ether (α-O-4 bonds), and the full conversion was achieved after 2 h at a temperature of 60 °C, with phenol and toluene as the sole reaction products. In addition, the conversion of more robust β-O-4 ether bonds in 2-phenoxy-1-phenylethanol reached up to 100% with the yield of ethylbenzene and phenol at 150 °C for 2.5 h being 60.2% and 68.3%, respectively. The reusability-experiment results indicate that Ni–CeO2/CN maintained a high catalytic activity in five reaction runs, making this a promising route for C–O ether bond cleavage under mild conditions.
研究领域:
催化化学
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生物质转化
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材料科学
✓ 已验证
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
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Xing Yi,Yan Wang,Zongpeng Zou,Yuan He,Li Lv,Wenxiang Tang,Tao Zhang,Shengwei Tang
The microreactor coupled mini-channel microdroplets extraction and separation technology (MES) was developed by adding polyvinyl alcohol (PVA) into microdroplets, realizing the controllable synthesis of a series of mono-component and multi-component metal oxide nano particles (MONPs). A double-layer surfactant structure composed of Span20 (oil phase surfactant) and PVA (water phase surfactant) was designed as a barrier to intercept and collect the precipitated salt at the microdroplet interface, the addition of PVA reduces the loss of salt components during the extraction process from 41.7 wt% to 1.1 wt%. The size control of mono-component MONPs (CuO, Co 3 O 4 , and NiO) was achieved using MES method. Furthermore, in the application direction of preparing multi-component MONPs, the advantages of MES in preparing multi-component catalysts (Ni/CeO 2 ) were verified. TEM, XRD, H 2 -TPR, CO 2 -TPD, XPS, BET et al. characterizations have shown that Ni entered the lattice of CeO 2 during precipitation to form a Ni-O-Ce solid solution and was therefore highly dispersed in CeO 2 . Ni/CeO 2 -MES showed high CO 2 conversion and CO selectivity in reverse water gas shift (RWGS) testing compared to Ni/CeO 2 catalysts prepared by impregnation method which has excellent thermal stability and can maintain over 99 % CO selectivity even after 50 h of reaction at 600 °C. The MES method was proved to be an efficient synthesis technology for MONPs and can be extended to a variety of metal oxides catalysts.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2020
·
IF 7.216
Shuangxi Lin,Ziwen Hao,Jindong Shen,Xiao Chang,Shouying Huang,Maoshuai Li,Xinbin Ma
The metal-support interaction is of critical importance to enhance the catalytic activity and selectivity. However, it is still challenging to construct an appropriate interaction starting from the catalyst fabrication and/or activation. We herein established low-temperature treatment of Ni 2+ ions impregnated on ceria in reductive atmosphere and reduction–oxidation cycles as effective approachs to regulate the metal-support interaction and raise the catalytic performance in the CO 2 methanation. The proposed construction approach yielded Ni/CeO 2 that displayed highly dispersed Ni nanoparticles in contact with CeO 2 (111) and (100) facet, higher density of surface oxygen vacancies and larger amounts of weak basic sites relative to the reference samples, which increased the capacity for H 2 and CO 2 adsorption/activation. The interaction resulted in appreciably (2–3 fold) higher activity in the CO 2 methanation with maintaining almost full selectivity to CH 4 and high stability. Coverage of Ni surface by CeO 2− x thin layer as a typical structure of strong metal-support interaction resulting from high-temperature reduction, can be alleviated via reduction–oxidation cycles. We also demonstrate the activation treatment-determined metal-support interaction effect can generally extend to (TiO 2 and ZrO 2 ) supported Ni catalysts.
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
危险品化学品经营许可证（带存储）