Journal of the Taiwan Institute of Chemical Engineers
·
2016
·
IF 2.848
Huan Liu,Zhen Ma
LaPO 4 has been used as a support to make supported catalysts in some investigations, but the effect of different LaPO 4 supports on the catalytic performance of supported catalysts has been rarely reported. In this work, conventional hexagonal LaPO 4 (LaPO 4 H) was prepared by precipitation, and hexagonal LaPO 4 nanowires (LaPO 4 HNW) was prepared by hydrothermal synthesis at 150 °C. Monoclinic LaPO 4 nanowires (LaPO 4 -MNW-220 and LaPO 4 -MNW-900) were prepared by hydrothermal synthesis at 220 °C or calcining LaPO 4 HNW at 900 °C. These samples were used to support Rh 2 O 3 via impregnation using Rh(NO 3 ) 3 as a precursor. The activities of these supported catalysts in N 2 O decomposition and CO oxidation follow the same sequence of Rh 2 O 3 / LaPO 4 HNW > Rh 2 O 3 / LaPO 4 H > Rh 2 O 3 / LaPO 4 -MNW-220 > Rh 2 O 3 / LaPO 4 -MNW-900, i.e. , two hexagonal LaPO 4 supports are better than two monoclinic LaPO 4 supports in making active catalysts, and hexagonal LaPO 4 nanowires are better than hexagonal LaPO 4 composed of nanoparticles and short nanorods. The most active catalyst has highly dispersed Rh 2 O 3 species interacting strongly with the support, more oxygen-adsorption capacity, and more basic sites.
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
Catalysis Science & Technology
·
2025
·
IF 4.2
Yilin Zhao,Fangwei Liu,Jingbo Hu,Yang Yang,Jianzhou Wu,Shihui Zou,Jie Fan
The Mn–Na2WO4/SiO2 catalyst for oxidative coupling of methane (OCM) is highly appealing and promising but its high light-off temperature (>800 °C) hinders its industrial application. Engineering catalysts for efficient catalytic performance is attractive yet challenging. In this study, we demonstrate that the incorporation of small amounts of silver into the Mn–Na2WO4/SiO2 catalyst significantly improves its performance, achieving a C2 yield of up to 20% at 750 °C. Characterization results indicate that silver facilitates O2 activation and promotes C–H bond activation, thereby further enhancing CH4 conversion. The findings offer valuable insights into advancing the design concept of high-performance OCM catalysts.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2021
·
IF 13.084
Yong Xu,Xuchun Wang,Di Yang,Zeyuan Tang,Muhan Cao,Huicheng Hu,Linzhong Wu,Lijia Liu,John McLeod,Haiping Lin,Youyong Li,Yeshayahu Lifshitz,Tsun-Kong Sham,Qiao Zhang
The conversion of light alkanes to olefins (e.g., ethylene, propylene, or butylene) is crucial to the chemical industry. ZrO2 with oxygen vacancies has recently been regarded as a promising catalyst for the direct dehydrogenation of light alkanes. However, the intrinsic mechanism of the effect of oxygen vacancies on catalytic performance has not been completely understood yet, and ZrO2 without promoters generally displays poor activity toward the direct dehydrogenation of light alkanes. In this work, we demonstrate that the oxygen vacancies in ZrO2 can be poisoned by H atoms during the dehydrogenation of light alkanes, and we report a strategy for stabilizing the oxygen vacancies in ZrO2 by Ga2O3. Experimental results and theoretical calculations indicate that ZrO2 with oxygen vacancies is responsible for dehydrogenation, while Ga2O3 prevents the poisoning of oxygen vacancies by dissociated hydrogen atoms which, in the absence of the Ga2O3 component, blocks further dehydrogenation. Consequently, the optimal Zr0.26Ga1 catalyst exhibits superior propane dehydrogenation performance to the industrial Pt–Sn catalyst, the state-of-the-art catalyst for the direct dehydrogenation of light alkanes. We anticipate this work may shed light on both the fundamental research of catalysis and the chemical industry.
研究领域:
催化化学
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材料科学
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工业化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Juntian Niu,Ziwei Jin,Baihe Guo,Haiyu Liu,Yan Jin,Jingyu Ran
Methane (CH 4 ) is a key component of natural gas and is essential for energy production and utilization. However, due to its strong greenhouse effect, efficient catalytic combustion methods are needed to convert it into CO 2 and H 2 O. This study systematically evaluates the catalytic performance of Co, CoO, and Co 3 O 4 in methane catalytic combustion, particularly highlighting the superior activity of Co 3 O 4 . To improve catalytic efficiency, this paper examines the effects of SiO 2 , Al 2 O 3 , and CeO 2 as support materials using co-precipitation and impregnation methods. The results show a significant improvement in the catalytic activity of Co 3 O 4 supported on CeO 2 , attributed to CeO 2 's unique redox properties and high oxygen storage capacity. Additionally, the study explores the impact of different loading amounts (5%, 10%, 15%, 20%) of Co 3 O 4 (x)-CeO 2 catalysts on their performance. The optimal 10%wt Co 3 O 4 –CeO 2 catalyst achieves methane conversion rates of 10%, 50%, and 90% at temperatures of 376 °C, 473 °C, and 578 °C, respectively, demonstrating exceptional stability during a 20-h stability test and the ability to adapt to fluctuations in CH 4 concentrations in low-oxygen environments, while also exhibiting significant catalytic activity across a range of methane concentrations from 0.5% to 2.5%. These findings provide important theoretical and experimental guidance for the application of cobalt-based catalysts in CH 4 combustion, paving the way for future catalyst design and optimization.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
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IF 7.4
Yanli Zhang,Jian Li,Jianyu Cai,Shuangye Li,Xing Fan,Liyun Song,Ruixue Guo,Jiasheng Liu
In this study, a series of γ-Fe 2 O 3 -modified V 2 O 5 -MoO 3 /TiO 2 (VMT) catalysts was prepared by wet impregnation method. The γ-Fe 2 O 3 -modified catalysts exhibited excellent catalytic performance, and 1.25 wt% γ-Fe 2 O 3 content improved the deNO x efficiency at 150 °C from 54% (unmodified VMT catalyst) to 84% (modified catalyst). BET, XRD, XPS, NH 3 -TPD, H 2 -TPR, and in situ DRIFTs were employed to characterize the physicochemical properties and reaction mechanisms of the catalysts. The introduction of γ-Fe 2 O 3 increased the V 5+ /V 4+ ratio, surface chemisorbed oxygen content, redox ability, and a number of acid sites in the prepared catalysts. XPS confirmed the addition of γ-Fe 2 O 3 introduced new charge transfer pathways (Fe 3+ /Fe 2+ ↔ V 5+ /V 4+ ). In situ DRIFTs suggested that the addition of γ-Fe 2 O 3 to the catalyst significantly increased the adsorption capacity of catalyst for NH 3 and NO x , while also exerting a strong activating effect on the adsorbed NH 3 . Furthermore, selective catalytic reduction over the VMT and 5PEG@1.25Fe-VMT catalysts followed the Eley-Rideal (E-R) mechanism. At temperatures above 200 °C, the 5PEG@1.25Fe-VMT catalyst also followed the Langmuir-Hinshelwood (L-H) mechanism.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Yu Qiu,Enkang Fu,Feng Gong,Rui Xiao
Ammonia is a prospective fuel for hydrogen storage and production, but its application is limited by the high cost of the catalysts (Ru, etc. ) to decompose NH 3 . Decomposing ammonia using non-precious Ni as catalysts can therefore improve its prospects to produce hydrogen. This work proposes several Ni/MgAl 2 O 4 with the support properties tuned and investigates the support effect on the catalytic performance. Ni/MgAl 2 O 4 -LDH shows high NH 3 conversion (∼88.7%) and H 2 production rate (∼1782.6 mmol g −1 h −1 ) at 30,000 L. kg −1 h −1 and 600 °C, which is 1.68 times as large as that of Ni/MgAl 2 O 4 -MM. The performance remains stable over 30 h. The characterizations manifest that the high specific surface area of Ni/MgAl 2 O 4 -LDH can introduce highly dispersed Ni on the surface. Kinetics analysis implies promoted NH 3 decomposition reaction and alleviated H 2 poisoning for Ni/MgAl 2 O 4 -LDH. A roughly linear relationship is obtained by fitting the curves of dispersed Ni on the surface vs the reaction orders regarding H 2 and NH 3 . This indicates that enhanced NH 3 decomposition performance can be ascribed to the strengthened NH 3 decomposition reaction and weakened H 2 poisoning by the highly dispersed Ni on the MgAl 2 O 4 -LDH surface. This work provides an opportunity to develop highly active and cost-effective catalysts to produce hydrogen via NH 3 decomposition.
研究领域:
化学工程
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能源科学
✓ 已验证
DOI
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 16
·e202405818
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IF 2
Gideon Kofie,Yin Fengxiang,Xu Rongji,Wu Qinxi
Graphical This study examines NdCoO 3 perovskite catalysts synthesized via solution combustion using citric acid for ammonia decomposition. The best performing catalyst 1.25:1NdCoO 3 -700 exhibits 96% conversion at 550 °C and a hydrogen production rate of 30 mmol·g⁻¹·min⁻¹. High basicity, optimized pore structure, and surface properties enhance the performance highlighting NdCoO 3 ’s potential for efficient hydrogen production. The decomposition of ammonia to produce hydrogen requires an efficient catalyst to lower the energy demand for this reaction. This study investigates the performance of NdCoO 3 in enhancing ammonia decomposition for hydrogen production. The NdCoO 3 perovskite is synthesized using the solution-combustion method with citric acid as fuel. The performance evaluation of the catalysts is conducted in a fixed-bed reactor. The catalysts are characterized by establishing the relationship between structure and activity. A fuel-to-metal ratio of 1.25:1 and a calcination temperature of 700 °C result in a catalyst with favorable physicochemical attributes. The catalyst 1.25:1NdCoO 3 -700 is obtained, which achieves 96% ammonia conversion at 550 °C, with a hydrogen generation rate of 30.6 mmolgcat −1. min −1 , making it the most active catalyst with an apparent activation energy ( E a ) of 64.47 KJ mol −1 . The surface analysis reveals that variations in surface basicity and favorable porosity affected the activity of the 1.25:1NdCoO 3 -T catalysts. The fuel-to-metal ratio and the calcination temperature are key factors influencing the activity of the NdCoO 3 catalyst.
研究领域:
材料科学
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催化化学
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能源转化
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
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IF 19.503
Chao Feng,Qianqian Gao,Gaoyan Xiong,Yanfei Chen,Yuan Pan,Zhaoyang Fei,Yanpeng Li,Yukun Lu,Chenguang Liu,Yunqi Liu
The low defect content and poor oxygen mobility of perovskite catalysts limit its application in VOC elimination. Herein, we report a strategy involving defect engineering route following an easy urea treatment method to enhance the propane oxidation performance of perovskite catalysts. The constructed LaCoO 3 -D43 exhibits superior catalytic activity (T 90 = 309.3 °C), the T 90 value is 150 °C lower than that of LaCoO 3 , and excellent thermal stability against CO 2 and H 2 O. Experimental results revealed that the urea pyrolysis resulted in the generation of La and O defects and rich surface-active Co species in high-valence states, increasing the utilization of Co active sites. DFT calculations show that the exposed Co surface is conducive to the adsorption and dissociation of oxygen and propane. This work provides a defect engineering strategy to effectively activate perovskite catalysts performance, and can be generalized for the fabrication of other types of perovskite catalysts.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Qingjing Liu,Ruisheng Wang,Ranjia Li,Xiaosheng Wang,Suoqi Zhao,Changchun Yu
Mn–Na2WO4-based catalysts with different supports were prepared using the incipient wetness impregnation method and evaluated for their oxidative coupling of methane (OCM) reaction performance. The results demonstrated that the SiO2- supported catalyst exhibited the best catalytic performance, and the introduction of H2O further enhanced its activity. Under the conditions of a feed gas mixture of CH4/O2/H2O = 6:1:24 at 800 °C and atmospheric pressure, the CH4 conversion and C2+ selectivity over the Mn–Na2WO4/SiO2 catalyst increased from 28.4% and 77.4% (without H2O) to 33.2% and 84.9%, respectively. In contrast, the catalytic activity using TiO2 and MgO supports drastically declined. Characterizations using X-ray diffraction (XRD), in situ infrared spectroscopy (In-situ IR), X-ray photoelectron spectroscopy (XPS), hydrogen temperature-programmed reduction (H2-TPR), and oxygen temperature-programmed desorption (O2-TPD) revealed that the introduction of steam not only served as a diluent to decrease the partial pressures of the reactants CH4 and O2, thereby reducing deep oxidation reactions in the gas phase, but also interacted with surface oxygen species (O22–) and silica to form adjacent surface-bonded disilanol free radicals Si–OIH. This interaction facilitated the dehydrogenation and coupling of two methane molecules on the catalyst surface, resulting in the generation of C2+ products, significantly enhancing the catalytic activity and selectivity of OCM.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Surfaces and Interfaces
·
2021
·
IF 4.837
Ikram Ullah,T.A. Taha,Asma M. Alenad,Ikram Uddin,Asif Hayat,Ashiq Hayat,Muhammad Sohail,Ahmad Irfan,Javid Khan,Arkom Palamanit
In this study, sulfated zirconia with loading of platinum (Pt) and platinum alumina (PA-Al 2 O 3 ) promoted sulfated zirconia (SZ) catalysts were synthesized by hydro-thermal route. The samples were characterized by XRD, BET, FT-IR, NH 3 -TPD, and TGA. The catalytic efficiency of all the synthesized catalysts was tested on the isomerization of n -butane. The results indicated that the conversion of n -butane (71.04%), selectivity to i -butane (98.96%), and yield of i -butane (70.30%) is significantly high for PA/SZ sample than that of Pt modified SZ and bare SZ. The results of this study suggest that the SZ modified by Pt/Al 2 O 3 (PA) provided better catalytic performance and higher stability (within 25 h of TOS), when compared with SZ, and Pt-modified SZ.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Mengting Wang,Jiajun Yang,Bo Chi,Jian Pu,Jian Li
La 0.8 Ce 0.2 Mn 0.6 Ni 0.4 O 3 with (LCMN@CuO) and without (LCMN) CuO addition are prepared by solution methods, followed by reduction in 5% H 2 –N 2 stream at 650 °C to form Ni exsolved and CuO reduced catalysts, LCMN@Ni and LCMN@Ni/Cu, for ethanol (EtOH) steam reforming (ESR). The catalysts are characterized by X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM), temperature programmed reduction (H 2 -TPR), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy etc., and are evaluated for ESR with a steam/carbon ratio of 3 and a weight hourly space velocity (WHSV) of 4 h −1 at temperatures between 500 and 700 °C. Ni exsolution and CuO reduction are confirmed on the substrates in LCMN@Ni and LCMN@Ni/Cu. Both the catalysts demonstrate a complete conversion of EtOH, forming mainly H 2 , CO 2 , CO and CH 4 . And increasing temperature to 700 °C increases the yields of H 2 and CO to the levels about 90% and 40%, respectively, at the cost of CH 4 ; and such performance remains unchanged for 30 h. These results indicate that both LCMN@Ni and LCMN@Ni/Cu are promising catalysts for ESR, the main difference between them is that the latter is more chemically stable and more resistant to carbon deposition under ESR conditions.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2015
·Vol. 8
·期 2
·512-522
·
IF 7.01
Hou Pengfei,Cui Penglei,Liu Hui,Li Jianling,Yang Jun
Noble metal nanoparticles with hollow interiors and customizable shell compositions have immense potential for a wide variety of applications. Herein, we present a facile, general, and cost-effective strategy for the synthesis of noble metal nanoparticles with hollow structures, which is based on the inside-out diffusion of Ag in solid-state core-shell nanoparticles. This approach starts with the preparation of core-shell nanoparticles with Ag residing in the core region, which are then loaded on a solid substrate and aged in air to allow the inside-out diffusion of Ag from the core region, leading to the formation of monometallic or alloy noble metal nanoparticles with a hollow interior. The synthesis was carried out at room temperature and could be achieved on different solid substrates. In particular, the inside-out diffusion of Ag calls for specific concern with respect to the evaluation of the catalytic performance of the Ag-based core-shell nanoparticles since it may potentially interfere with the physical and chemical properties of the core-shell particles.
研究领域:
材料科学
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化学工程
·
纳米技术
✓ 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）