EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY
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2022
·Vol. 124
·期 9
·2100254
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IF 3.196
Kainan Xing,Minghe Cao,Qinkai Zhu,Haojie Yin,Meizhen Lu,Jianbing Ji
Vegetable oils and their derivatives are of great interest because of their abundance and renewability. This paper prepares nonanal (N) and methyl 9-oxonanoate (M) from methyl epoxystearate (ME) with WO 3 ∙0.33H 2 O, WO 3 ∙H 2 O, and WO 3 ∙2H 2 O as catalysts and H 2 O 2 as the oxidant without the use of organic solvent. The reaction temperature, catalyst amount, H 2 O 2 amount, and reaction time effects on ME conversion and N/M yield are investigated. The results show that WO 3 ∙H 2 O has the best catalytic performance. The optimal reaction conditions are: reaction temperature 60 °C, reaction time 40 min, ME/H 2 O 2 /WO 3 ∙H 2 O molar ratio 1/1.2/0.4, under which the ME conversion and N/M yield reach 95% and 70%, respectively. WO 3 ∙ n H 2 O reacts with H 2 O 2 to form soluble tungsten anions, resulting in severe tungsten loss. Al-MCM-41 materials with different silicon to aluminum molar ratios are added to the reaction system as adsorbents to recover the catalyst by effective adsorption of tungsten anions. The adsorption performance improves as the Si/Al ratio decreases, however, the ME conversion and N/M yield decrease. Thus, 50 is the most suitable Si/Al ratio. The ME conversion and N/M yield can still reach 90% and 60% after four times of use. Practical applications : The nonanal has a natural fragrance and can be used in the cosmetic industry as well as in the preparation of bio-based surfactants. The methyl 9-oxonanoate can be converted into polymer monomers by hydrogenation or amination. The results show that WO 3 ∙ n H 2 O has good catalytic activity, and a satisfying yield of aldehyde products is obtained under mild reaction conditions.
研究领域:
化学工程
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可再生资源化学
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DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 40
·23061-23070
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IF 3.049
Libo Peng,Qinglong Xie,Yong Nie,Xuejun Liu,Meizhen Lu,Jianbing Ji
The oxidative cleavage of vegetable oils and their derivatives to produce bio-based aldehydes is a potentially useful process, although the aldehyde products are readily oxidized to carboxylic acids and thus seldom obtained in high yields. The present study developed a room-temperature method for the synthesis of bio-aldehydes via the oxidative cleavage of vegetable oil-derived epoxides, using H2WO4 as the catalyst, H2O2 as the oxidant, and t-BuOH as the solvent. Reactions were carried out at temperatures ranging from 25 to 35 °C for 3.5–10.5 h, and provided >99% conversion and >90% aldehyde yield. In particular, an approximately 97% yield was obtained at 25 °C after 10.5 h. As the reaction proceeded, the H2WO4 dissolved to form a W-containing anion. Several mesoporous Al-MCM-41 materials having different Si/Al ratios were hydrothermally synthesized and used as adsorbents to recover the catalyst by adsorbing these anions. The adsorption capacity of the Al-MCM-41 was found to increase with decreases in the Si/Al ratio. The Al-MCM-41 had little effect on the oxidative cleavage reaction at 25 °C, and thus could be directly added to the reaction system. The excellent anion adsorption performance of the Al-MCM-41 greatly improved the reusability of the H2WO4 catalyst. When using the Al-MCM-41 with the best adsorption performance, there was no significant decrease in the activity of the catalyst following five reuses.
研究领域:
化学工程
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生物化学
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材料科学
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DOI
PubMed
高影响因子
Materials Today Sustainability
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2025
·
IF 7.9
Haoran Li,Qisong Yi,Yuanchao Shao,Haimei Xu,Zichun Wang,Yuanshuai Liu
The sustainable transformation of renewable biomass into value-added chemicals is essential to addressing global environmental and energy challenges. Among these, the production of 5-hydroxymethylfurfural (HMF) from biomass-derived glucose is of considerable interest for both scientific and industrial applications. In this study, mesoporous aluminium incorporated MCM-41 catalysts (Al-MCM-41) were synthesized using an ultrasonic-assisted method at room temperature. Their ordered mesoporous structure was preserved even with high concentrations of Al. The catalysts' acidity was finely tuned by varying the Si/Al ratio, enabling the development of an optimal catalyst to enhance the glucose-to-HMF conversion via Brønsted and Lewis acid catalysis. Characterization techniques, including XRD, TEM, N 2 adsorption-desorption, NH 3 -TPD, Py-FTIR, 29 Si and 27 Al MAS NMR, were employed to evaluate the catalysts’ structure and acidity. The results revealed that ultrasonic-assisted synthesis strategy improves Al dispersion, optimizes acid site density, and significantly enhances HMF yield and selectivity. The best-performing Al-MCM-41-10 catalyst can afford ∼90 % glucose conversion with ∼60 % HMF selectivity at 160 °C, and displays excellent reusability under the applied reaction conditions. This study provides valuable insights into designing efficient catalysts for biomass conversion and underscores the broad applicability of the ultrasonic-assisted synthesis method for other heteroatom-doped mesoporous materials, such as Sn-MCM-41.
研究领域:
催化化学
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生物质能
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材料科学
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DOI
高影响因子
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
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2015
·Vol. 2015
·期 12
·2125-2131
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IF 2.942
Chunyan Sun,Feng Zhang,Xiao Wang,Fangqin Cheng
Graphical A composite ammonium molybdophosphate/Al-MCM-41 material is synthesized by a one-pot method with natural clay as the silica and aluminum source. A modified “liquid-phase transport” step allows the use of impure natural clay as the starting material to produce pure product without sedimentation pretreatment. The composite material is effective for the adsorption of cesium ions from brine. Ordered hexagonal mesoporous aluminosilicate matrix (Al-MCM-41) with incorporated ammonium molybdophosphate (AMP) was successfully synthesized by a one-pot synthesis method with natural clay from low-grade potash ores of Qinghai salt lake as the silica and aluminum source. We introduced a modified “liquid-phase transport” step, which allowed the use of impure natural clay as a starting material to directly produce pure product without sedimentation pretreatment. The resultant product was characterized by X-ray fluorescence (XRF) spectroscopy, FTIR spectroscopy, XRD, TEM, 27 Al and 31 P magic-angle spinning (MAS) NMR spectroscopy, and N 2 adsorption/desorption, which indicated that the AMP was immobilized in the mesoporous structure of Al-MCM-41. The adsorption capacity of the final product for the removal of cesium ions in solution was also investigated. The results suggested that salt lake clay is a promising low-cost precursor for the production of mesoporous aluminosilicate supports through one-pot syntheses, and the final composite material is effective for the adsorption of cesium ions from solutions containing other alkali metal ions.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
RSC Advances
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2017
·Vol. 7
·期 75
·47539-47546
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IF 3.108
Song Zhang,Chao Xu,Guoqing Zhai,Mingliang Zhao,Mo Xian,Yuxiang Jia,Zongjiang Yu,Fusheng Liu,Fangfang Jian,Weizhi Sun
A new type of bimetallic palladium and aluminum incorporated mobile crystalline materials (Pd–Al-MCM-41) as bifunctional catalysts has been hydrothermally synthesized. Characterization shows that these molecular materials exhibit an ordered mesoporous structure, high surface area and a good dispersion of palladium in the frame. The catalytic activity of the Pd–Al-MCM-41 for the dimerization–hydrogenation reaction system of β-pinene in one pot has been systematically studied. Pd0.5–Al30-MCM-41 (SiO2/Al2O3 = 30, 0.5 wt% palladium content) was found to be the best catalyst which gave a dimer yield of up to 64.7%. It is worth noting that palladium shows a good synergic catalytic effect with aluminum in the dimerization reaction and enhances the dimerization yield. Furthermore, the bifunctional catalyst displayed a good activity over 4 runs.
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
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2021
·Vol. 22
·期 12
·6540
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IF 5.924
Xu Zhang,Tao Du,He Jia
In this study, four different coal fly ashes (CFAs) were used as raw materials of silica and alumina for the preparation of the alumina-containing Mobil Composition of Matter No. 41 (Al-MCM-41) and the exploration of an activation strategy that is efficient and universal for various CFAs. Alkaline hydrothermal and alkaline fusion activations proceeded at different temperatures to determine the best treatment parameters. We controlled the pore structure and surface hydroxyl density of the CFA-derived Al-MCM-41 by changing the crystallization temperature and aging time. The products were characterized by small-angle X-ray diffraction, nitrogen isotherms, Fourier-transform infrared spectroscopy,29Si silica magic-angle spinning nuclear magnetic resonance, and transmission electron microscopy, and they were then grafted with thiol groups to remove Pb(II) from aqueous solutions. This paper innovatively evaluates the CFA activation strategies using energy consumption analysis and determines the optimal activation methodology and parameters. This paper also unveils the effect of the crystallization condition of Al-MCM-41 on its subsequent Pb(II) removal capacity. The results show that the appropriate selection of crystallization parameters can considerably increase the removal capacity over Pb(II), providing a new path to tackle the ever-increasing concern of aquic heavy-metal pollution.Keywords:coal fly ash;CFA activation;Al-MCM-41;crystallization parameters;Pb(II) removal capacity
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
ChemSusChem
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2022
·Vol. 15
·期 7
·e202200099
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IF 9.14
Xinyu Lu,Haoquan Guo,Jiajia Chen,Duoying Wang,Adam F. Lee,Xiaoli Gu
Graphical Oil upgrading : This study investigates the efficient deoxygenation of lignin extracted from Chinese fir sawdust via oxidative delignification to sustainable liquid fuels rich in alkyl guaiacols through in-situ catalytic transfer hydrogenation using isopropanol, formic acid, and NiMo/Al-MCM-41 as organic solvent, internal hydrogen donor, and hydrodeoxygenation catalyst, respectively. Efficient deoxygenation of lignin-derived bio-oils is central to their adoption as precursors to sustainable liquid fuels in place of current fossil resources. In-situ catalytic transfer hydrogenation (CTH), using isopropanol and formic acid as solvent and in-situ hydrogen sources, was demonstrated over metal-doped and promoted MCM-41 for the depolymerization of oxygen-rich (35.85 wt%) lignin from Chinese fir sawdust (termed O-lignin). A NiMo/Al-MCM-41 catalyst conferred an optimal lignin-derived oil yield of 61.6 wt% with a comparatively low molecular weight ( M w =542 g mol −1 , M n =290 g mol −1 ) and H/C ratio of 1.39. High selectivity to alkyl guaiacols was attributed to efficient in-situ hydrogen transfer from isopropanol/formic acid donors, and a synergy between surface acid sites in the Al-doped MCM-41 support and reducible Ni/Mo species, which improved the chemical stability and quality of the resulting lignin-derived bio-oils.
研究领域:
化学工程
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催化
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可再生能源
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生物燃料
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DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2021
·
IF 5.541
Fangqi Wang,Fengwen Yu,Yi Wei,Ao Li,Shenzheng Xu,Xianghong Lu
Oleaginous biomass conversion to liquid hydrocarbon biofuels has emerged as an effective solution to the energy crisis and environmental problems. In this process, the removal of oxygenated compounds will directly affect the effectiveness of subsequent biofuel applications. Herein, deoxygenation of oleic acid by catalytic cracking was conducted using five various elements (La, Ni, P, Zr and Ce) modified Al-MCM-41. The related characterizations were carried out for these catalysts, including N 2 physisorption, XRD, XPS, pyridine-FTIR and NH 3 -TPD techniques. The results showed the mesoporous structure of Al-MCM-41 was maintained after different modifications, and these catalysts greatly improved the hydrocarbons content and physiochemical properties of biofuels. The modified catalysts tended to facilitate the decarbonylation pathway and showed high selectivity to alkane and aromatic hydrocarbons. Besides, La/Al-MCM-41 presented excellent anti-coking activity. Ni/Al-MCM-41 showed both high dehydrogenation and deoxygenation activities. The Zr modification and Ce modification had a promotion effect in the deoxidizing activity of the catalyst, owing to the formation of oxophilic metal oxides. Noteworthily, P/Al-MCM-41 displayed the best deoxidizing performance due to its high Brönsted acidity, which caused the highest hydrocarbons content (82.30 %) and the lowest fatty acids content (around 0 %) of the biofuel. Moreover, the resulting biofuel had not only low oxygen content (3.88 wt.%) and acid value (5.47 mgKOH g −1 ) but also a high calorific value (44.50 MJ kg −1 ), which could be processed into green diesel. Hence, the catalytic cracking of fatty acid over P/Al-MCM-41 has excellent potential to produce high-quality renewable fuels.
研究领域:
化学工程
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可再生能源
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催化
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生物化学
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DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
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2021
·Vol. 100
·期 7
·1558-1568
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IF 2.007
Jian Chen,Mengjing Zhu,Fuwei Xiang,Junfeng Li,Hongjun Yang,Zhipeng Mao,Ganggang Chang,Shaoping Li
(2-methyl-6-ethylphenyl)-1-methoxypropyl-2-imine (MEMI) is an important intermediate for the synthesis of commercial pesticide S-metolachlor. However, the research on heterogeneously catalytic kinetics of MEMI, and further the catalytic distillation simulation aiming at continuous operation, have never been reported. Herein, the catalytic kinetics for the synthesis of MEMI by HPW/Al-MCM-41 have been systematically investigated, and further fitted by using a pseudo-homogeneous kinetic model, based on which, the reaction equilibrium constant, activation energy, and rate constant are obtained. Furthermore, simulation of the continuous process of MEMI synthesis was carried out using the software Aspen Plus V10. Sensitivity analysis of operating parameters such as feed stage, distillation rate, number of reactive theoretical stages, and the best operating conditions were also obtained. An excellent product purity (>98.9%) of MEMI could be achieved when operated at the optimum conditions. Compared with the batch method, catalytic distillation provided continuous synthesis of MEMI, and the reaction was more thorough, achieving process integration and optimization. Our results provide substantial theoretical and empirical supports for the industrial synthesis of MEMI.
研究领域:
化学工程
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催化反应工程
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DOI
高影响因子
RSC Advances
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2017
·Vol. 7
·期 14
·8677-8687
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IF 3.108
Guoxia Yun,Qingxin Guan,Wei Li
Although HDS and HDN reactions over transition metal phosphides have been widely studied, few publications about aromatic hydrodearomatization (HDA) over transition metal phosphides are found. Using ordered mesoporous Al-MCM-41 (Al-M) as the support, a series of supported nickel phosphide catalysts with different Ni/P molar ratios and loadings have been prepared by a temperature-programmed reduction and characterized. The HDA activity of naphthalene was measured in a fixed bed reactor at 250–330 °C and 3 MPa. The results showed that the catalyst with initial Ni/P molar ratio of 1.25 and 15 wt% loading displayed the highest HDA activity as well as 99.0% of selectivity of decalin at 270 °C, which is even higher than that of 0.5 wt% Pt–Al-M catalyst. As a comparison, the HDA performance of various catalysts was also examined. The results revealed that the presence of framework aluminum favors HDA processes and a synergistic effect between nickel phosphide and the suitable acidity resulted in an improvement of the catalytic activity. Finally, the possible reaction pathway of naphthalene hydrogenation (HYD) on nickel phosphide catalysts was proposed. Taking into consideration the high catalytic activity, Al-M supported nickel phosphide can be considered as a very efficient HDA catalyst to decrease the contents of aromatics in the fuels.
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
JOURNAL OF CHROMATOGRAPHY A
·
2020
·
IF 4.049
Wenli Zhu,Jing Zhang,Xiaowan Zhang,Lizhen Han,Peige Qin,Shufang Tian,Qian Zhou,Xuebin Zhang,Minghua Lu
The Al-doped mesoporous crystalline material-41 (Al-MCM-41) composite was prepared and applied as fiber coating material of headspace solid-phase microextraction (HS-SPME) for extraction of polycyclic aromatic hydrocarbons (PAHs) from human urine. Five PAHs including acenaphthene, fluorene, phenanthrene, anthracene, and pyrene are chosen as target analytes to evaluate the performance of the material by GC-FID analysis. The mesoporous Al-MCM-41 composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption measurement, and thermogravimetric analysis. The parameters affecting the extraction efficiency of HS-SPME were investigated. Under the optimal conditions, the method exhibits ideal linearity for target analytes in the range of 0.3–600 ng⋅mL -1 with the coefficients (R 2 ) equal or higher than 0.9906. The enrichment factors are calculated from 540 to 1760. The limits of detection (LODs) and limits of quantitation (LOQs) are between the ranges of 0.06–0.18 and 0.3–0.9 ng⋅mL -1 , respectively. The relative standard deviations (RSDs) ( n = 5) of intra-day and inter-day are in the ranges of 1.08–7.49% and 2.84–18.3% respectively. The fiber-to-fiber reproducibility ( n = 3) is in the range of 6.47–13.9%. The method was successfully applied for the analysis of PAHs in human urine with reasonable recoveries which is ranging from 73.29 to 116.1%.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
Foods
·
2026
·Vol. 15
·期 10
·1738
·
IF 6
Yu Wang,Chengming Wang,Guowei Ling,Mingshuang Xia,Yuhan Yi,Shilin Liu,Wenlin Li
Traditional activated clay (AC) bleaching usually shows limited adsorption selectivity, leading to micronutrient loss during pigment removal, and also suffers from high residual oil retention and poor regenerability. Developing mild bleaching materials with both high adsorption efficiency and selectivity is therefore important for oil refining. Mesoporous Al-MCM-41 (AM) adsorbents with different Si/Al ratios were prepared and characterized in pore structure and acidity, and the bleaching performance against AC in terms of pigment removal and the retention of micronutrients in rapeseed oil and the bleaching mechanism were studied. The results showed that AM25 (Si/Al = 25) exhibited the best overall performance among the AM samples under the tested conditions (70 °C, 20 min). It achieved a bleaching efficiency of 92.3% and removed 94.56% of chlorophyll, 92.94% of lutein, and 84.09% of β-carotene. In addition, AM25 reduced the peroxide value from 2.52 to 0.58 mmol/kg. High retentions of tocopherols (93.89%), phytosterols (98.73%), and squalene (96.32%) were also observed. Meanwhile, the adsorption rates of α-tocopherol, brassicasterol, and α-linolenic acid showed the highest values in their relative homologues of tocopherols, phytosterols, and free fatty acids (FFAs), respectively, due to differences in the methyl amount of tocopherols, the side-chain unsaturation of phytosterols, and the fatty acid chain unsaturation of fatty acids. Furthermore, the kinetic and isotherm data for chlorophyll and carotenoids were better described by the pseudo-second-order and Freundlich models, respectively. Combined with thermodynamic analysis, they indicated that adsorption was a spontaneous, endothermic, entropy-driven, heterogeneous multilayer process dominated by physical adsorption. Further, pigment adsorption was mainly governed by uniform mesopores and Si–OH/Si–OH–Al sites in AM. Among them, carotenoid removal depended primarily on the dispersion effect of moderately strong acid sites within pore-confined regions, whereas chlorophyll removal was more sensitive to the number of acidic sites in AM. AM25 still maintained 83.31% bleaching efficiency after five regeneration cycles. These performances of AM25 are significantly superior to that of AC.
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PubMed
高影响因子
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