INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2025
·
IF 3.9
Bowen Tan,Danru Xu,Mengmeng Jin,Bolun Yang,Zhun Hu,Jingjun Liu
Cerium dioxide (CeO2) with different morphologies was synthesized via a hydrothermal method and applied to the carbonylation of glycerol with CO2. Subsequent characterization through H2-TPR and catalytic activity tests demonstrated that CeO2 nanorods exhibited the highest oxygen storage/release capacity as well as enhanced catalytic performance compared to other morphologies. CeO2 nanorods were thus further modified through hydrogen reduction at varying temperatures, aiming to tune the density of the oxygen vacancies. Characterization via BET, NH3-TPD, CO2-TPD, XPS, and ESR indicated that variations in morphology and reduction temperature influenced the microstructural characteristics and the strength of the acid–base sites of the catalysts. Notably, hydrogen reduction created more oxygen vacancies in the CeO2 nanorods, with the concentration of these vacancies increasing with higher reduction temperatures. Furthermore, the catalytic activity of CeO2 in glycerol carbonylation with CO2 showed a positive correlation with the concentration of oxygen vacancies. Optimizing CeO2 catalysts can enhance its performance in activating CO2, providing new ideas for industrial CO2 resource utilization and carbon capture technology development.
研究领域:
催化化学
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材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2019
·
IF 3.25
Zepeng Lv,Dong Liu,Yijie Wu,Run Zhang,Haibo Sun,Jie Dang,Liwen Hu
Tungsten, one of the refractory metals, has lots of excellent properties, making tungsten powders become a choice of raw material for many applications. This work reported a simple method (the salt-assisted hydrogen reduction of WO 3 powders) for preparing tungsten powders with desired morphologies and size. By adjusting the amount of additive (Y(NO 3 ) 3 ) and reduction temperature, metallic tungsten particles with different morphologies and size were obtained. It was found that both temperature and additive had apparent effects on the morphology and size of metallic W particles, and the large parallelepiped-shaped powders disappeared and large irregular blocky-shaped powders were degraded under the influence of additive. With the increase of temperature and amount of salt, particles became more dispersed and the size increased at higher temperatures, and the shape of particles was changed from spherical to polyhedral as well. On the contrary, the size of sub-particles became smaller as increasing amount of Y(NO 3 ) 3 at lower temperatures. Based on the results, the reaction and refining mechanisms for preparing tungsten were proposed as well.
研究领域:
材料科学
·
冶金学
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2019
·Vol. 21
·期 21
·5828-5840
·
IF 9.405
Xinli Tong,Pengfei Guo,Shengyun Liao,Song Xue,Haigang Zhang
The selective transformation of the aldehyde group (–CHO) in multifunctional oxygenates is a key challenge in the development of sustainable biomass feedstock. Herein, a smart Ni-MFC catalyst was developed from a 2D Ni-based metal–organic framework (MOF), which efficiently promoted the transformation of –CHO in the presence of H2 to a methyl group (–CH3) via the reductive etherification and hydrogenolysis of the C–O ether bond in methanol. Moreover, the catalytic process could be controlled to directionally produce methyl ether (–CH2OR) using the reductive etherification protocol. For the catalytic reduction of vanillin, the Ni-MFC-700 catalyst guaranteed the full conversion of vanillin and 96.5% yield of the desired 2-methoxy-4-methylphenol (MMP), while the Ni-MFC-500 catalyst afforded about 82.7% yield of 4-(methoxymethyl)-2-methoxyphenol in methanol solvent. This is a novel and promising approach for the valorization of multifunctional oxygenates and biomass-derived platform compounds.
研究领域:
化学催化
·
生物质转化
·
有机合成
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2023
·
IF 3.6
Meng-Chao Li,Lu Wang,Zheng-Liang Xue
The influences of different parameters, such as reaction temperature, yttrium (Y) content, and H 2 concentration, on the particle size and morphological structure of Mo powder prepared via the H 2 reduction of MoO 2 , were investigated in the work. TG, XRD , FE-SEM, laser particle size analysis , model fitting, and orthogonal design experiment methods were adopted to analyze the reaction kinetic and reduction mechanism. The results showed that the optimum conditions for preparing ultrafine Mo powder were recognized as 1073 K, 1 mass% Y content, and a H 2 concentration of 0.000576 mol·cm −2 ·min −1 , which enabled the as-prepared Mo powder with a particle size as small as 107 nm. A new interfacial chemical reaction model with the consideration of reaction temperature, H 2 concentration, and sample thickness, was proposed to analyze the reaction kinetic. It was found that the curves predicted by the model agreed well with the experimental data, with the apparent activation energy extracted to be 94.686 kJ/mol. The effect of different individual parameter on the reaction rate and the possible reduction mechanism were also elucidated.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
VACUUM
·
2024
·
IF 3.8
Ping-guo Jiang,Xiong-gang Lu,Wang-jun Peng,Hong Liu,Yao Zhu,Cai-song Yan,Jing-rong Zhao
This study investigates the structural evolution of blue tungsten reduction products when exposed to hydrogen under controlled water vapor partial pressures. The reduction of WO₂.₉ was achieved through hydrogen atom diffusion at 1050 °C. The Results indicate that, at low water vapor partial pressure, the reduction process of blue tungsten initiates on the surface and progresses inward, creating surface cracks on the clusters. These cracks enable water vapor to interact with the reduced tungsten (W) at their base, leading to the formation of needle-like WO₂.₇₂ phases that grow outward. Under high water vapor partial pressure, the morphology of the acicular WO 2.72 phase changes to a stacked structure. Additionally, W-OH bonds were identified in the reduction products, with the WO₂.₇₂ growth angles observed at approximately 12° relative to the tungsten particles, closely matching the interfacial model prediction of 13.41°. The results of this paper will provide theoretical support for the structural evolution of intermediate products during hydrogen reduction of blue tungsten.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2024
·
IF 4.2
Xiao Liu,Lu Wang,Zheng-Liang Xue
The hydrogen reduction of MoO 2 is a common method for preparing ultrafine molybdenum powder, which is an important basic material for manufacturing high-performance Mo-based alloys. However, its preparation parameters are usually hard to be controlled. To address this issue, the work conducted the parameter optimization research during the hydrogen reduction process with using central composite design method, and the influence of different parameters such as reaction temperature, yttrium content, and hydrogen flow rate, on the particle size and oxygen content of the prepared molybdenum powder were investigated. The findings showed that the particle size of the prepared molybdenum powder is gradually decreased with the increase of reaction temperature and yttrium content, while gradually increased with the increase of hydrogen flow rate. The oxygen content of the prepared molybdenum powder is gradually decreased with the increase of reaction temperature and hydrogen flow rate, while gradually increased with the increase of yttrium content. Reaction temperature and yttrium content have significant interactions on the particle size and oxygen content are also concluded, and their respective regression model equations are obtained. The result also demonstrated that the particle size and oxygen content of the prepared molybdenum powder had a certain contradictory relationship. Through the comprehensive analysis, the optimal parameters for preparing ultrafine molybdenum powder with a low oxygen content are deduced, that is, reaction temperature: 1200 K, yttrium content: 0.1 mass%, and hydrogen flow rate: 1000 mL/min. Under the conditions, the average particle size and oxygen content of the prepared molybdenum powder are 320 nm and 0.456 mass%, respectively.
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
Materials Research Express
·
2019
·Vol. 6
·期 12
·126586
·
IF 1.449
Zhuangzhi Wu,Xin Liu,Dezhi Wang
A traditional preparation process of Mo powder is generally time-consuming and leads to coarse particles. In this work, we propose a short-flow strategy, in which the intermediate product of MoO2 is prepared by a one-step self-reduction method in air instead of a mixture of decomposition and hydrogen reduction processes. And the reaction mechanism of self-reduction is investigated and the consequent sintering performance of Mo powder is also compared with the traditional one. The obtained results demonstrate that the finally synthesized Mo–La2O3 powder prepared by the self-reduction strategy are spherical with an average particle size of 2.03 μm, exhibiting an excellent sintering performance with a relative density of 95.3% and a hardness of 260.6 (HV), better than those by a traditional one (93.4% and 232.4 (HV)), which can be attributed to smaller particle size and better shapes. This work provides a new route for the synthesis of Mo–La2O3 powder, indicating a possible industrial application.
研究领域:
材料科学
·
冶金工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Minjie Chen,Chaohuang Chen,Qianhai Zhou,Hui Jin,Xiaohong Hu,Chen Miao,Kaijian Sang,Jiang Xu,Saiyong Zhu,Daohui Lin
Nanoscale zero-valent iron (nZVI) is a promising material for pollution remediation, but its practical application is limited by the lack of scaling up preparation method and the high cost of raw materials. In this study, the ball-milling method is used to prepare nanoscale iron oxide prior to high temperature H 2 -reduction, producing ball-milled and then H 2 -reduced nZVI ( BM−RE ZVI). It is demonstrated the strained iron oxide crystals after ball-milling increased the specific surface area, while the high-temperature H 2 -reduction process decreased iron vacancy. In this way, the ball-milling strain and the high-temperature H 2 -reduction together facilitated the exposure of (200) Fe planes (i.e. [100] Fe direction) of the obtained BM−RE ZVI, thereby enhancing reactivity. Compared to commercial nZVI (C-nZVI), BM−RE ZVI was characterized by abundant surface Fe 0 , more reactive crystal planes, and fewer iron vacancies, enabling flexible electron transfer. The reaction rate constants normalized with Fe 0 content ( k Fe 0 ) for removing aqueous Pb, Cr, trichloroethylene (TCE), and florfenicol (FF) increased by 3.3, 2.6, 10.5, and 11.9 times, respectively, as compared to C-nZVI, and the fastest 100 % FF removal was achieved in a real groundwater sample. In addition to its environmental friendliness, BM−RE ZVI was also economically viable according to the environmental friendliness and techno-economic analyses, with an estimated price of 27 k-32 k ¥ ton −1 . These findings provide a new approach for preparing economical and eco-friendly nZVI, which will boost its application in practical pollution remediation
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 29
·e202301223
·
IF 2.1
Yingwei Li,Shengxin Chen,Ying Jin,Xinxin Li,Ruirui Zhang,Ruixia Liu
Graphical A simple and controllable defect construction method for vanadium-oxygen catalysts through hydrogen reduction with TCD detector were used to control the reduction state of CHR-VOx which determines the V-Species and O-Species. Furthermore, the structure-performance relationship and the catalytic pathway were assumed, multi-liganded-oxygen and V 4+ species are the key parameters. A series of controlled-hydrogen-reduction VO x (CHR-VO x ) were prepared after our controllable hydrogen treatment, and CHR-VO x were controlled to be reduced to the states dominated by V 5+ and V 4+ species, subsequently the catalytic roles of V-species and O-species for cyclohexane (CHA) oxidation were explored. As expected, the surface properties of CHR-VO x have occurred remarkable change resulting in a significantly improvement on catalytic performance determined by V-species and O-species. The reduction behavior of the properties was recognized by XPS and Raman. Generally, the moderate-reduced CHR-VO x which possessed most 78.7 % multi-liganded-oxygen ( L O) performed the best conversion for CHA (11.8 %), and the over-reduced CHR-VO x with a large content of V 4+ species (33 %) performed a best selectivity for adipic acid (44.3 %). In this case, L O sites were regarded as the active site to accelerate the activation of CHA, while V 4+ species were regarded as the oxygen vacancies (OVs) through V 4+ −OV to contribute to the further oxidation to adipic acid.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 7
·3953-3958
·
IF 3.43
Jingbo Qi,Xun Hu
The reduction of ZnO in a ZnO-supported catalyst to metallic zinc, the alloying of metallic zinc with a second metal and the evaporation of zinc species in a reductive atmosphere of hydrogen was investigated in this study. The results show that the reduction temperature was the determining factor for the transformation of zinc species. The complete removal of ZnO in a ZnO-supported catalyst can be achieved at 700 °C. The effects of different metals supported on ZnO on the transformation of ZnO were also investigated. Cu, Co and Ni species can slow the ZnO loss due to the priority for the reduction of these metal oxides and the formation of metal–Zn intermetallics. Fe based catalysts noticeably accelerated the loss of ZnO, which can be ascribed to the high oxophilicity of Fe and the strong interactions between the metal and support.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
Materials
·
2025
·Vol. 18
·期 10
·2315
·
IF 3.2
Songya Feng,Anxin Gao,Zihang Ma,Hongjie Xu,Zhiyong Xue
The general polyol methods used for synthesizing copper nanoparticles (CuNPs) usually require high temperatures to ignite the reduction reaction, which leads to the difficulty of controlling the particle size. Herein, a new polyol method for the size-controllable synthesis of CuNPs at low temperatures by adopting high-pressure hydrogen as the reductant is verified. It is proven that hydrogen is capable to reductively produce CuNPs at temperatures as low as 120 °C. The size of the CuNPs can be controlled between 19.29 nm and 140.46 nm by adjusting the hydrogen pressure, the reaction temperature, and duration. An empirical relationship between temperature and particle size is proposed. This work verifies a low-temperature strategy to synthesize nanoparticles with good size-controllability.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2024
·
IF 4.2
Hengli Li,Huijun Shang,Feng Pan,Weijun Li,Zhan Du
This article investigated the preparation of ultrafine W powder by fluidized bed hydrogen reduction, and the apparent activation energy was determined for various reduction stages by using temperature programmed reduction with hydrogen. The results demonstrate that the introduction of Co 3 O 4 significantly enhances the reduction process of WO 3 .High Co 3 O 4 content can lead to the formation of CoWO 4 in the initial stage and obtain products with high content of Co 3 W. An increase in the Co 3 O 4 content correlates with a gradual decrease in the particle size of the product. The apparent activation energy for the WO 3 → WO 2 and WO 2 → W processes decreases as the Co 3 O 4 content increases. It can be decreased from 105.59 kJ /mol to 78.72 kJ/mol for the WO 3 → WO 2 stage, and from 107.38 kJ/mol to 78.38 kJ/mol for the WO 2 → W stage, respectively.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）