SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Jiaxin Li,Yifei Liang,Zhao Li,Ke Fan,Chunxue Wang,Kai Li,Yuan Li,Xin Sun,Ping Ning,Fei Wang
The synthesis of methane from syngas represents a pivotal technology in the artificial synthesis of natural gas, with the study of methanation catalysts being a fundamental aspect of this process. Extensive research has focused on CO methanation using Ni/Al 2 O 3 catalysts; however, enhancements in catalyst stability and low-temperature activity are still required. This research investigated the structure of Ni/Al 2 O 3 under H 2 reduction at varying temperatures and the catalytic performance in natural gas synthesis (SNG) through CO methanation. It was observed that a higher reduction temperature resulted in nickel species agglomeration. Notably, Ni catalysts reduced at 600 °C demonstrated optimal CO conversion and CH 4 selectivity under the tested conditions. Characterization studies uncovered a synergistic effect between Ni and NiO species, which was most effective for catalytic activity under hydrogen reduction at 600 °C but only at an appropriate reduction temperature. These insights are significant for the advancement of Ni/Al 2 O 3 methanation catalysts in natural gas production .
研究领域:
化学工程
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催化科学
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DOI
高影响因子
Catalysts
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2016
·Vol. 6
·期 5
·63
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IF 2.964
Yunfei Qi,Haiyun Yu,Quan Cao,Bo Dong,Xindong Mu,Aiqing Mao
Nickel is found to demonstrate high performance in the amination of cyclohexanol into cyclohexylamine in water and two solvents with low boiling points: tetrahydrofuran and cyclohexane. Three catalysts, Raney Ni, Ni/Al2O3and Ni/C, were investigated and it is found that the base, hydrogen, the solvents and the support will affect the activity of the catalyst. In water, all the three catalysts achieved over 85% conversion and 90% cyclohexylamine selectivity in the presence of base and hydrogen at a high temperature. In tetrahydrofuran and cyclohexane, Ni/Al2O3exhibits better activity than Ni/C under optimal conditions. Ni/C was stable during recycling in aqueous ammonia, while Ni/Al2O3was not due to the formation of AlO(OH).Keywords:nickel;cyclohexanol;cyclohexylamine;base;hydrogen
研究领域:
化学工程
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催化
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有机化学
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DOI
高影响因子
CATALYSIS LETTERS
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2023
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IF 2.8
Chen Yiming,Hou Zhanggui,Wang Chuan,Ma Xin,Yang Hong,Wang Wen,Zhou Ling,Zhang Yi
As well known, the industrial methanation process needs highly active and stable catalysts obtained from cheap and abundant elements. In this work, we propose a high-loaded Ni/Al 2 O 3 catalyst promoted by manganese. Among them, the 20Ni2Mn/Al 2 O 3 catalyst exhibits the best CO 2 conversion (90.5%) and excellent methanation stability at 250 °C. In addition, the roles of the Mn promoter on CO 2 conversion and selectivity were investigated in detail. The features of natural and promoted catalysts are described through XRD, XRF, BET, TEM, H 2 -TPR, CO 2 -TPD, and operando DRIFTS techniques. Based on various characterization results, the addition of Mn will greatly reduce the Ni particle size and improve the Ni dispersion on the alumina support. Furthermore, compared to the unpromoted catalyst, Mn promoted catalysts show better reducibility and have more medium basic sites. And these medium basic sites are favorable to the adsorption and activation of CO 2 . In-situ DRIFTS experiments for CO 2 methanation reveal that manganese could promote the monodentate carbonate hydrogenated to formate rapidly, which could be faster converted towards CH 4 , contributing to significantly improved activity of the Mn promoted Ni/Al 2 O 3 catalyst. Graphical Abstract
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2026
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IF 3.5
Chaoyue Zhang,Mingrui Wang,Xinyue Han,Zheng Shen,Hongying Zhuo,Tianyu Zhang,Xiaofeng Yang,Yanqiang Huang
Metastable hcp-Ni enables the synthesis of highly dispersed and stable Ni/Al 2 O 3 catalyst • Highly dispersed Ni/Al 2 O 3 catalyst delivers 75.7% CO 2 conversion and 100-h stability • Original hcp-Ni particles spontaneously transform into fcc-Ni clusters of ∼2.3 nm • Small Ni clusters promote CO 2 methanation via monodentate formate intermediate • Fcc-Ni precursors undergo severe sintering to ultra-large and less-active particles Ni-based catalysts are promising candidates for CO 2 methanation while their practical applications are limited by particle agglomeration and deactivation. Here, we report a facile strategy to fabricate a highly dispersed and stable Ni/Al 2 O 3 catalyst using metastable hexagonal close-packed (hcp)-Ni as a precursor. Comprehensive characterization reveals that the initial hcp-Ni (∼12.0 nm) spontaneously transforms into uniform face-centered cubic (fcc)-Ni nanoparticles (NPs) of ∼2.3 nm on γ -Al 2 O 3 support during H 2 reduction and CO 2 methanation reaction. The small Ni particles contribute to improved Ni 0 proportion on catalyst surface. In contrast, the original fcc-Ni precursors are prone to sintering, forming ultra-large and less-active Ni aggregates. The highly dispersed Ni NPs derived from hcp-Ni enhance CO 2 adsorption-activation and facilitate the formate-mediated reaction pathway. The resulting hcp-Ni/Al 2 O 3 catalyst delivers a CO 2 conversion of 58.2% with a CH 4 selectivity of 85.4% at 460 °C and endows robust stability exceeding 100 hours. The optimal CH 4 space time yield reaches 179.5 mmol·g cat −1 ·h −1 , exceeding 2.4 times that of fcc-Ni/Al 2 O 3 . This work establishes a reliable synthesis paradigm rooted in crystal-phase regulation, enabling the manufacture of highly dispersed and stable Ni-based catalysts for efficient CO 2 methanation. Manufacturing Highly Dispersed and Stable Ni/Al 2 O 3 Catalysts from hcp-Ni for Enhanced CO 2 Methanation Download: Download high-res image (221KB) Download: Download full-size image
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高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2024
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IF 3.7
Yutong Pan,Pengju Gao,Shixiong Tang,Xiaoyu Han,Ziwen Hao,Jiyi Chen,Zhenmei Zhang,Heng Zhang,Xiaohui Zi,Maoshuai Li,Shiwei Wang,Yue Wang,Xinbin Ma
This work synthesized a series of Ni/CeO 2 /Al 2 O 3 catalysts with varying CeO 2 doping amounts to enhance low-temperature CO 2 methanation. The introduction of CeO 2 weakens the interaction between Ni and Al 2 O 3 , leading to the formation of Ni-CeO 2 active sites. This results in a high dispersion of Ni and CeO 2 , improved catalyst reducibility, increased number of active sites, and enhanced the CO 2 methanation. This work further investigated the impact of WHSV and catalyst stacking configuration to enhance the reaction. When the catalyst is stacked into three segments with a temperature gradient of 330 °C, 300 °C, and 250 °C under WHSV=9000 ml·h –1 ·(g cat) –1 , the CO 2 conversion significantly increases to 95%, which is remarkably close to the thermodynamic equilibrium (96%).
研究领域:
化学工程
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催化科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2022
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IF 7.139
Yang Xu,Yingying Zhu,Pengfei Shen,Geng Chen,Xinbao Li
An improved method for hydrogen production by the steam reforming of phenol over novel fly ash-based catalysts is investigated. The Ni/Al 2 O 3 -ash catalysts are prepared by an equal-volume impregnation method and characterized by XRD , FESEM , BET and H 2 -TPR techniques. The effects of various process parameters including mixing ratio of fly ash, temperature, support, gas hourly space velocity (GHSV) and steam-to-carbon molar ratio (S/C) on the catalytic activity are investigated. The results show that fly ash mixing at 50 wt% and choosing γ-Al 2 O 3 as the support own the best performance. A maximum hydrogen yield of 83.8% is achieved at 450 °C with a S/C of 10 and a GHSV of 4968 h −1 with a maximum phenol conversion of 98.6%. The stability of the Ni-ash1-γA1 catalyst is further investigated and it is shown to continuously and stably react for more than 20 h at 450 °C with excellent catalytic reaction stability.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
ENERGY CONVERSION AND MANAGEMENT
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2026
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IF 10.9
Shiying Yang,Fan Jiao,Xiaotong Fan,Lixinyu Mei,Xiaojing Shi,Qibin Liu
Methane carbon cyclic reforming (MCCR) represents a novel dry methane reforming (DMR) reaction, offering advantages in terms of greenhouse gas utilization and automatic product separation. This study dedicated to exploring the potential of the MCCR method for continuous and long-term production of H 2 and CO fuels. Using a self-synthesized Ni/Al 2 O 3 catalyst, we elucidated at the microscopic level the advantages of directional conversion of carbon and hydrogen elements during the MCCR process, as well as its underlying mechanism. Through in-situ testing and microscopic characterization, it was confirmed that the decoupling of the MCCR reaction can suppress side reactions, and prevent excessive graphitization of carbon deposits and promote their removal by switching reaction mechanisms promptly. The long-term continuous fuel production experiment was conducted at the macroscopic level for validating these findings. The catalyst’s stability was confirmed by 2750 min of continuous TGA cycling tests, maintaining a carbon removal ratio of 99.99% after 250 cycles. This performance was further validated in a fixed-bed reactor, where an average H-C ratio of 1.13 was sustained over 40 cycles during a 20-hour long-term test. This research paves the way for the advancement of MCCR technology and complements conventional DMR methods for the production of clean fuel.
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高影响因子
APPLIED ENERGY
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2019
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IF 8.426
Mingzheng Liao,Ying Chen,Zhengdong Cheng,Chao Wang,Xianglong Luo,Enqi Bu,Zhiqiang Jiang,Bo Liang,Riyang Shu,Qingbin Song
One of the most attractive routes for hydrogen production for fuel cell applications is partial oxidation of hydrocarbons. However, exothermic partial oxidation reaction tends to cause local overheating of the reaction bed therefore reducing catalytic activity. In this study, hydrogen production by partial oxidation of propane over Ni/Al 2 O 3 based catalyst with the addition of SiC was experimentally investigated. Both packed bed mixing and bulk doping methods were introduced to study the effect of SiC for its high thermal conductivity and high temperature stability. The as-prepared samples were characterized by a variety of measurements. Due to the high temperature stability of SiC particles in the bulk regions, stacking dual porous-like structures were formed after calcination by doping SiC into Ni/Al 2 O 3 with certain ratios. From the results, local overheating of the catalyst bed generated by the exothermic reactions was relieved by SiC addition for both cases. Ni/Al 2 O 3 -SiC (30 wt% SiC) catalyst performed a higher hydrogen production of 236 μmol/g cat . s and kept stable for 20 h at 600 °C compared to mechanical mixing method. Aggregation of Ni content and carbon deposition of the spent catalyst of SiC-containing catalysts were reduced compared to Ni/Al 2 O 3 . As can be seen from the morphological and non-isothermal kinetics, the carbon deposited on Ni/Al 2 O 3 -SiC catalyst that caused catalyst deactivation was more easily activated for removal due to SiC content with high thermal conductivity.
研究领域:
化学工程
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能源科学
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2021
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IF 7.033
Enkang Fu,Yu Qiu,Huaichang Lu,Sijun Wang,Lishan Liu,Hanjun Feng,Yanxin Yang,Zizhan Wu,Yunlong Xie,Feng Gong,Rui Xiao
Ammonia (NH 3 ) has been regarded as an attractive energy source for hydrogen production via catalytic decomposition , especially over non-noble metal catalysts . Owing to the decent performance and low cost, nickel (Ni) based catalysts have been widely studied for catalytic decomposition of NH 3 where the decomposition rates, can be further tailored by adding other metals. Herein, we synthesized bimetallic M(M = Co, Fe, Cu)Ni/Al 2 O 3 catalysts delivering superior catalytic performance at a wide temperature range of 350–750 °C. Co-Ni/Al 2 O 3 demonstrated nearly 100% conversion of NH 3 decomposition to H 2 at 700 °C and the gas hourly space velocity of 30,000 ml g −1 min −1 , which was ~20.85% higher than that of intrinsic Ni/Al 2 O 3 . The structural characterizations indicated that Co could decrease the particle size and enhance the dispersion of active sites. The density functional theory calculations substantiated that the associative decomposition of N to generate N 2 was the rate-determining step of the NH 3 decomposition reactions . NH 3 Temperature Programmed Desorption (TPD) results suggested that the enhanced catalytic performance was predominantly attributed to the Co that decreases the energy barrier for the associative decomposition of N to form N 2 . This study provides new insights in designing diverse catalysts for efficient NH 3 decomposition for controllable H 2 production.
研究领域:
催化化学
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能源材料科学
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DOI
高影响因子
MOLECULES
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2026
·Vol. 31
·期 3
·420
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IF 4.6
Yu Jiang,Xiaoli Pan,Jifeng Pang,Pengfei Wu,Qinggang Liu,Mingyuan Zheng
The selective hydrogenolysis of glucose into 1,2-propanediol (1,2-PG) constitutes a significant yet challenging transformation in biomass valorization, as it involves a highly coupled network of isomerization, C-C bond cleavage, and hydrogenation steps. Herein, a highly efficient Ni-CeO2catalyst supported by basic Al2O3is developed via a urea-assisted precipitation strategy. Systematic catalytic evaluation and comprehensive characterization reveal that this synthesis method markedly enhances Ni dispersion and hydrogen activation capacity, while CeO2modification modulates the electronic state of Ni and introduces strong Lewis basic sites associated with oxygen vacancies. The synergistic interplay between Ni and CeO2effectively promotes glucose isomerization and retro-aldol condensation while maintaining sufficient hydrogenation activity. As a result, the optimized catalyst achieves a 1,2-PG yield of 45.1% with over 99% glucose conversion under optimal hydrothermal reaction conditions. Moreover, the catalyst exhibits relatively stable catalytic performance over four consecutive runs. This work elucidates key structure–activity relationships in multifunctional Ni-based catalysts and provides design principles for efficient biomass-derived polyol production.
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DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Kang Li,Chunlei Pei,Xinyu Li,Sai Chen,Xianhua Zhang,Rui Liu,Jinlong Gong
The modulation of the interaction between the active metal and the underlying support material plays a key role and remains a challenge in many important catalytic reactions. This paper describes a new method for the modification of Ni/Al 2 O 3 by La 2 O 2 CO 3 , which is responsible for modulating the interaction between Ni and the Al 2 O 3 support. When La 2 O 2 CO 3 is loaded on the Al 2 O 3 support as a La 2 O 3 precursor, combined with XRD, H 2 -TPR, H 2 -pluse chemisorption, Raman spectroscopy and TEM characterization, it is found that La 2 O 2 CO 3 can prevent Ni from entering the alumina support and forming NiAl 2 O 4 . This strategy allows more Ni to be reduced and exposed as active sites. Consequently, the La 2 O 2 CO 3 modified Ni/Al 2 O 3 exhibited superior activity with respect to the reference La 2 O 3 modified Ni/Al 2 O 3 and original Ni/Al 2 O 3 in dry reforming of methane (DRM). At the same time, La can cover the acidic sites of alumina and increase the alkalinity of the catalyst, thereby promoting carbon dioxide adsorption and activation, and inhibiting carbon deposition. In addition, the introduction of La also inhibits the sintering of Ni under harsh reaction conditions by enhancing the interaction between Ni metal and the support. This modification method can simultaneously improve the reactivity and stability of the catalyst by altering the interaction between the metal and the support.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
ACS Catalysis
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2022
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IF 13.7
Rui Ma,Junxian Gao,Jiajing Kou,David P. Dean,Christian J. Breckner,Kaijun Liang,Bo Zhou,Jeffrey T. Miller,Guojun Zou
Nickel has been considered a promising nonprecious metal for propane dehydrogenation (PDH) because of its appealing ability to activate alkane molecules; however, synthesis of selective and stable Ni sites remains a challenge. Herein, we describe an alumina-supported isolated Ni(II) site by settling Ni2+ cations into Al3+ vacancy on γ-Al2O3 as a selective and stable Ni-based catalyst for PDH. Based on the results from combined characterizations, including in situ X-ray adsorption spectroscopy (XAS), scanning transmission electron microscopy (STEM), and in situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS), atomically dispersed Ni(II) sites with bonding to oxygen ions from the alumina support are demonstrated. PDH catalyst tests shows that the Ni(II) single-site catalyst delivers superior performance compared to a supported metallic Ni NP catalyst, possessing >93% propylene selectivity at considerable propane conversions (15–45%), which surpasses Ni nanoparticle (NP) catalysts. The correlation of selectivity to propylene on different Ni structures with the structural characterizations suggest that the coordinatively unsaturated tetrahedral Ni(II) sites facilitate the desorption of propylene, which inhibits the side reactions for coking. Moreover, the atomically dispersed Ni(II) sites remain in its local structure in the reaction-regeneration cycles, as evidenced by in situ XAS. This study on alumina-supported nickel catalysts affords insights into the nature of selective and stable nickel sites involved in the PDH reaction.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）