FUEL
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2015
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IF 3.52
Haimei Xu,Zhichao Miao,Huahua Zhao,Jian Yang,Jun Zhao,Huanling Song,Ning Liang,Lingjun Chou
In this paper, a series of ordered mesoporous zirconium oxophosphate with different P/Zr molar ratios (M-ZrPO- x ) were prepared via one-pot evaporation induced self-assembly strategy (EISA). The catalytic performance of M-ZrPO- x for the dehydration reaction of fructose to produce 5-hydroxymethylfurfural (5-HMF) was also studied. With high concentration of Brönsted and Lewis acid sites measured through NH 3 -TPD and pyridine-IR, M-ZrPO-0.75 performed high catalytic activity (up to 97.4%) and selectivity (79.6%) of 5-HMF under relatively mild conditions. Furthermore, M-ZrPO-0.75 performed excellent catalytic stability. Based on detailed analyses of XRD, SEM, TEM, BET and XRF, the structural, surface and textural properties of M-ZrPO-0.75 after reaction were investigated. Obtained results demonstrated that the mesostructure still retained even after twelve cycles, which may be ascribed to the “ordered” mesoporous properties and high thermal stability. In addition, a lower activation energy was obtained in this M-ZrPO catalytic system using dimethyl sulfoxide as solvent.
研究领域:
化学工程
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催化
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材料科学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 21
·6185-6197
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IF 5
Hui Guo,Tingting Ge,Yuchao Li,Yuxia Li,Yanxia Zheng,Xinpeng Guo,Haofei Huang,Ming Wang,Cuncun Zuo
Organic solvent method was used to prepare the active component VPO, which was loaded on ball-milled γ-Al2O3 support. VPO/γ-Al2O3 catalysts were synthesized by in situ generation for the synthesis of acrylic acid (AA) by the aldol condensation of acetic acid (HAc) and formaldehyde (HCHO). The effects of the calcination temperature and the loading of the active component VPO on catalytic activity were systematically investigated. XRD, BET, SEM, CO2/NH3-TPD, FT-IR spectroscopy, and TG techniques were used to characterize the VPO/γ-Al2O3 catalysts. The results showed that the catalyst had the best crystal structure and acid–base activity center at a calcination temperature of 350 °C. The catalytic performance was evaluated using a fixed bed reactor. 60% VPO/γ-Al2O3 exhibited the highest reactivity, and the yield of AA was up to 51.5%. Response surface methodology (RAM) was used to optimize the reaction conditions for aldol condensation. The kinetic equation and reaction order of the aldol condensation reaction were determined using the VPO/γ-Al2O3 catalyst. It provides guidance for the in-depth study of aldol condensation reactions in the future.
研究领域:
催化
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化学工程
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材料科学
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物理化学
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产品关联
DOI
高影响因子
RSC Advances
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2016
·Vol. 6
·期 86
·82707-82715
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IF 3.289
Wei Li,Rui-tang Guo,Shu-xian Wang,Wei-guo Pan,Qi-lin Chen,Ming-yuan Li,Peng Sun,Shu-ming Liu
A series of Mn/CeSiOx catalysts were prepared by the wet impregnation method and used for selective catalytic reduction of NO with NH3. As can be seen from the experimental results, the Mn/CeSiOx catalyst with a Ce/Si molar ratio of 2/1 showed excellent low-temperature SCR activity, high N2 selectivity and excellent SO2 and H2O tolerance. The relationship between the CeSiOx support and the SCR performance of Mn/CeSiOx (2 : 1) catalyst was investigated based on the characterization results of N2 adsorption, XRD, XPS, H2-TPR, NH3-TPD and in situ DRIFT. The strong interaction between Ce and Si resulted in the good dispersion of Mn species on the support; correspondingly, the redox ability and NH3 adsorption capacity were greatly enhanced. The results of in situ DRIFT study revealed that the NH3-SCR reactions over Mn/CeO2 and Mn/CeSiOx (2 : 1) mainly obeyed both the E–R mechanism and the L–H mechanism. Furthermore, the formation of more Mn4+ and chemisorbed oxygen greatly facilitates the oxidation of NO to NO2, as a result, promoting the low-temperature SCR performance of Mn/CeSiOx (2 : 1).
研究领域:
催化
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环境科学
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化工
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2023
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IF 8.2
Xinyi Xing,Xian Shi,Mengya Ruan,Qichun Wei,Ying Guan,Hui Gao,Siquan Xu
Introduction of the sulfonic acid group into H-β zeolite to prepare β-SO 3 H bifunctional catalysts for the efficient synthesis of 5-hydroxymethylfurfural (HMF) from cellulose . Catalysts characterization, such as XRD, ICP-OES, SEM (Mapping), FTIR, XPS , N 2 adsorption-desorption isotherm, NH 3 -TPD, Py-FTIR demonstrate the sulfonic acid group was successfully grafted onto the β zeolite. A superior HMF yield (59.4 %) and cellulose conversion (89.4 %) was obtained in the H 2 O(NaCl)/THF biphasic system under 200 °C for 3 h with β-SO 3 H(3) zeolite as catalyst. More valuable, β-SO 3 H(3) zeolite converts other sugars and obtains ideal HMF yield, including fructose (95.5 %), glucose (86.5 %), sucrose (76.8 %), maltose (71.5 %), cellobiose (67.0 %), starch (68.1 %), glucan (64.4 %) and also converts plant material (25.1 % for moso bamboo and 18.7 % for wheat straw) with great HMF yield. β-SO 3 H(3) zeolite catalyst keeps an appreciable recyclability after 5 cycles. Moreover, in the presence of β-SO 3 H(3) zeolite catalyst, the by-products during the production of HMF from cellulose were detected, and the possible conversion pathway of cellulose to HMF was proposed. The β-SO 3 H bifunctional catalyst has excellent potential for the biorefinery of high value platform compound from carbohydrates.
研究领域:
催化
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化学工程
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材料科学
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生物化学
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可再生能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
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IF 8.355
Yan Cui,Lei Qin,Weiwei Kang,Jinghong Ma,Yongzhen Yang,Xuguang Liu
Magnetic carbon nanospheres (MCNSs) dotting with Fe 3 O 4 nanoparticles were synthesized by a simple solvothermal method. Furtherly, KOH activation and HNO 3 acidification of MCNSs were carried out to tune surface structure and property of MCNSs for the sake of adsorption improvement. The results show that both MCNSs and modified MCNSs (MCNSs-KH) have magnetic properties, and can be used as adsorbents for rapid separation and reutilization towards quinoline in coking wastewater. After KOH activation and HNO 3 acidification, the saturated adsorption capacity of MCNSs-KH is improved to 297.21 mg g −1 , much better than that of MCNSs (99.43 mg g −1 ). According to BET and NH 3 -TPD characterizations, KOH activation introduced a large number of pore structures, which significantly increased the specific surface area of MCNSs; HNO 3 acidification further increased the surface acidity of MCNSs, especially C O functional group, which promoted the acid–base interaction with weakly basic quinoline. From the results of adsorption kinetics, isotherm and thermodynamics, the spontaneous and exothermic adsorption process conformed to pseudo-second-order and Langmuir–Freundlich models better.
研究领域:
材料科学
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环境工程
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化学工程
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纳米技术
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产品关联
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
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2025
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IF 3.5
Li Xinyu,Li Jingqi,Li Na
This study investigated the effects of sequential acid treatment and phosphorus incorporation on the performance of Fe–Mn-Ce composite metal oxide catalysts. The FeMnCeO x catalyst was prepared using the sol–gel method and modified through two methods: treatment with phosphoric acid alone and a sequential treatment with phosphoric acid followed by sulfuric acid. The results show that the sequentially acid-treated catalyst exhibited over 90% NO x conversion and N 2 selectivity in the temperature range of 200–350 °C, outperforming other catalysts. Characterization analyses such as XRD and NH 3 -TPD revealed that acid modification enhanced the surface acidity and redox properties of catalysts. XPS analysis showed that sequential acid treatment increased the surface chemisorbed oxygen content of the catalyst and optimized its surface structure. In-situ DRIFTS spectroscopy further elucidated that the catalytic reaction follows both Langmuir–Hinshelwood and Eley–Rideal mechanisms concurrently.
研究领域:
环境科学
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催化化学
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材料科学
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化学工程
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 10
·5608-5616
·
IF 7.443
Chan Wang,Miao Yang,Peng Tian,Shutao Xu,Yue Yang,Dehua Wang,Yangyang Yuan,Zhongmin Liu
A spherical self-assembly of SAPO-34 nanosheets was hydrothermally synthesized by using a quaternary ammonium-type organosilane surfactant [3-(trimethoxysilyl)propyl]octadecyldimethylammonium chloride (TPOAC) as the mesoporogen and a part of the silica source, and diethylamine (DEA) as the microporous template. The prepared materials were well characterized by XRD, XRF, SEM, TEM, N2 adsorption–desorption, NH3-TPD, NH3-adsorbed IR and pyridine-adsorbed IR measurements. It revealed that the morphologies, compositions and acidity of the SAPO-34 products changed significantly with the increased TPOAC/TEOS ratio, showing that the TPOAC/TEOS ratio had a significant impact on the crystallization process of SAPO-34. Solid state 13C, 29Si NMR and TG-DTA analyses were further conducted to investigate the status of TPOAC in the final products. A possible crystallization process involving TPOAC was proposed. The catalytic performances of the synthesized SAPO-34s were evaluated using the MTO reaction. The optimal SAPO-34 nanosheet assemblies with a hierarchical porous structure displayed a remarkably enhanced catalytic lifetime and high yields of light olefins.
研究领域:
材料科学
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化学工程
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催化
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无机化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）