APPLIED SURFACE SCIENCE
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2025
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IF 6.9
Yakai Chen,Xinya Feng,Xiaohan Yu,Xingliang Xu,Jing Xu
Catalytic aldol condensation of biomass-derived furfural (FAL) with acetone (AC) into the single-condensation product 4-(2-furyl)-3-buten-2-one (FAC) is a potential and promising strategy for biomass improvement process and still challenging. Metal oxides exposed different crystal facets can regulate their surface structure and adsorption activation ability, which can provide an opportunity to enhance aldol condensation performance. Here, nanoparticles-CeO 2 (P-CeO 2 ), nanorods-CeO 2 (R-CeO 2 ) and nanocubes-CeO 2 (C-CeO 2 ) with (111), (110) and (100) plane predominant exposure was prepared to explore their catalytic performance for the aldol condensation of FAL with AC to obtain FAC. The serial detailed characterizations, experimental results and density functional theory calculation revealed that R-CeO 2 with a dominant (110) facet possesses appropriate surface adsorption energy, abundant oxygen vacancy (Ov) and excellent acid-base properties, which can effectively boost the adsorption and activation of FAL and AC and reduce the barrier of aldol condensation reaction based on the acid-base catalysis mechanism. The work would reveal the influence of CeO 2 crystal facet on the aldol condensation and provide a broad potential for the rational design of metal oxide catalysts for other acid-base catalytic reactions.
研究领域:
催化化学
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生物质能
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
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2018
·Vol. 149
·期 2
·373-389
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IF 2.911
He Teng,Qu Yixin,Wang Jidong
The catalytic performance of cesium oxide supported on three types of silica gel A-type (A-silica), B-type (B-silica) and C-type (C-silica) was tested for the aldol condensation of methyl acetate (Ma) and formaldehyde (FA) to methyl acrylate (MA). The catalysts were characterized using TEM, BET, XRD, FTIR, TG, XPS, and CO 2 -TPD and the reaction mechanisms were explored using DFT calculations. To obtain high selectivity of MA, appropriate amount of Cs loading is required since much higher loading of Cs leads to excessive decomposition of Ma and/or MA. On the Cs/silica, the Si–O–Cs species generated from the reaction of cesium oxide with silanol groups are the active sites as demonstrated by characterization and the DFT calculations. Silica gels with larger pore size and pore volume are preferred since these facilitate the contact of the reactants with active sites and provide higher capacity for accommodation of coke. As compared with Cs/SBA-15, Cs/B-silica seems more prospective for industrial application due to the lower cost of silica gel and even better performance. Graphical Abstract
研究领域:
催化化学
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理论计算化学
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产品关联
DOI
高影响因子
RSC Advances
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2015
·Vol. 5
·期 41
·32826-32834
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IF 3.84
Yanan Wang,Xuewei Lang,Guoqing Zhao,Huanhui Chen,Yiwei Fan,Linqing Yu,Xiuxiu Ma,Zhirong Zhu
A variety of cesium supported catalysts with amorphous SiO2 as a carrier were prepared by vacuum impregnation and ultrasonic impregnation methods, which were used for the synthesis of methyl acrylate by aldol condensation of methyl acetate and formaldehyde. The as-prepared catalysts were characterized by XRD, N2 adsorption–desorption, NH3-TPD, CO2-TPD, XPS, ICP and TG. The results indicated that the bifunctional Cs–La–Sb/SiO2 showed a high conversion of methyl acetate as well as a high yield of methyl acrylate, which was attributed to the weak acid–base sites and the formation of basic Cs–O–Si species with the addition of antimony and lanthanum, respectively. Furthermore, Cs–La–Sb/SiO2-(V) prepared by vacuum impregnation showed a high initial catalytic activity, but its activity sharply decreased due to the loss of active species. Comparatively, Cs–La–Sb/SiO2-(U) prepared by ultrasonic impregnation showed a good stability owing to the cavitation effect of ultrasonic waves. The conversion of methyl acetate and yield of methyl acrylate remained above 20% and 9.0% (based on methyl acetate) for 100 h without obvious deactivation. Moreover, carbon deposition was the main factor for the deactivation of Cs–La–Sb/SiO2-(U), and the coked catalyst could be regenerated by calcination in air.
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
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2017
·Vol. 7
·期 16
·3555-3561
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IF 5.773
Mingxue Su,Wenzhi Li,Tingwei Zhang,HaoSheng Xin,Song Li,Wei Fan,Longlong Ma
Aldol condensation reactions between furfural and acetone can be used to produce liquid fuel intermediates. It was found that tin-containing zeolites with MFI (Sn-MFI) and BEA* (Sn-Beta) framework structures are effective for C–C bond formation via the aldol condensation reactions between furfural and acetone. Aldol condensation between furfural and acetone produced two main products, 4-(2-furyl)-3-buten-2-one (FAc) and 1,5-di-2-furanyl-1,4-pentadien-3-one (F2Ac). Although both these catalysts were active for the aldol condensation reactions, different selectivities to aldol products were observed over Sn-MFI and Sn-Beta. FAc and F2Ac were formed over the Sn-Beta catalyst with selectivities to FAc of 40% and F2Ac of 22%, respectively. In contrast, only FAc was produced over Sn-MFI. The variation in selectivity is likely due to different pore geometries of Sn-Beta and Sn-MFI, suggesting that Sn-MFI exhibits shape selectivity for aldol condensation between furfural and acetone. In addition, it was found that the addition of water to the reaction system can also affect the product selectivity, leading to the aldol product exclusively being FAc over Sn-Beta.
研究领域:
化学工程
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催化科学
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可再生能源
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2021
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IF 4.311
Yanan Liu,Genkuo Nie,Shitao Yu,Lun Pan,Li Wang,Xiangwen Zhang,Chengxiang Shi,Ji-Jun Zou
Synthesizing high-performance jet fuels from lignocellulose-derived ketones through aldol condensation is significant for expanding the sources of jet fuel and promoting high-value conversion of biomass. The main problem in aldol condensation is that water generated in such a reaction will decrease the activity of the acid catalyst. Herein, we developed a highly stable, efficient, and water-tolerant SBA-16 confined phosphotungstic acid (HPW) catalyst and applied it to controllably catalyze cross-condensation of cyclopentanone and cyclohexanone. The surface of SBA-16 was modified by alkylimidazole, which creates a relatively hydrophobic environment and anchor points for HPW, leading to resistance to HPW leaching and maintenance of a stable performance for the catalyst. After hydrodeoxygenation, a high-performance fuel blend with a density of approximately 0.905 g/mL and a freezing point lower than −50 °C was obtained. This study provides a general method for preparing highly efficient and stable catalysts for reactions affected by water.
研究领域:
生物质能
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催化化学
✓ 已验证
DOI
高影响因子
Green Energy & Environment
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2020
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IF 6.395
Jiajun Liu,Kui Wu,Zhengke Li,Wensong Li,Yuqing Ning,Weiyan Wang,Yunquan Yang
The great challenge in the aldol condensation of tailored fermentation products (acetone–butanol–ethanol, ABE) into energy intensive fuels is to develop a suitable catalyst with high activity and low–cost. In this study, Co, Ni, and Co–Ni supported on Mg–Al oxide catalysts were prepared and their pore diameters were enlarged via adding active carbon as a hard template into Mg–Al hydrotalcite. During the aldol condensation reaction, the catalyst activity was enhanced after enlarging the pore diameter and Co–Ni bimetal supported catalyst presented the highest activity, which was resulted from that the electron transfer between Co and Ni in Co–Ni alloy enhanced the dehydrogenation activity and large pore lowered the mass transfer resistance. After optimizing the reaction conditions, acetone conversion and the total selectivity of C 5 –C 11 desired products in the aldol condensation of ABE reached up to 76% and 90%, respectively. The stability study showed that the activity was decreased with the increase of reaction number because of the oxidation of metallic Co and Ni, but this could be solved via a simple hydrogen reduction method.
研究领域:
催化化学
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能源科学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
·
IF 2.5
Meng Li,Diangen Zhou,Hualiang An,Shanshan Dong,Xinqiang Zhao,Yanji Wang
2-Ethylhexanal (2EH) is an important intermediate for the production of 2-ethyhexanoic acid (2-ETA), and studying the direct synthesis of 2EH through heterogeneous catalysis of n-butanal aldol condensation-selective hydrogenation reaction integration is of great significance for the industrial production of 2-ETA. Herein, a series of Pd/TiO2 catalysts were prepared and characterized by XRD, CO pulse adsorption, TEM, CO2/NH3-TPD and H2-TPR. Their catalytic performance for direct synthesis of 2EH from n-butanal was investigated in stainless steel autoclave first. The results showed that the Pd/TiO2 prepared by the excessive impregnation method, loaded with 0.5 wt.% of Pd, and reduced at 400 ℃ showed excellent catalytic performance: 95.4% conversion of n-butanal and up to 99.9% selectivity of 2EH. The particle size of Pd, the base strength and the amount of acid/base of the catalyst are the main factors affecting its catalytic performance. The smaller the particle size of Pd, the greater the base strength and the larger the amount of acid/base of the catalyst, the better its catalytic performance. Then the integrated reaction mechanism was established based on the results of characterization and FT-IR of online sampling. Furtherly, the continuity of the reaction process was achieved on fixed-bed reactor. Under the reaction conditions of a liquid hourly space velocity (LHSV) of 7.2 h-1, a reaction temperature of 190 °C and a H2 pressure of 3.2 MPa, the conversion of n-butanal and the selectivity of 2EH were 91.2% and 89.8%, respectively. During the continuous operation for 300 h under optimal conditions, the conversion of n-butanal decreased slightly first and then stabilized, while the selectivity of the target product 2EH remained basically unchanged.
研究领域:
催化化学
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工业化学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2024
·
IF 5.6
Shanshan Shao,Tianrui Sun,Xiaohua Li,Yifan Wang,Laixin Ma,Zhufeng Liu,Shiliang Wu
Due to the high molecular weight, high viscosity and strong instability of heavy bio-oil from rape straw, it is necessary to explore new high-value utilization methods. Heavy bio-oil based carbon material (HBC) was prepared via carbonization and activation assisted by pyrolysis gas, and the basic Mg-Zr-O catalysts using HBC as the carrier (Mg-Zr-O/HBC) was synthesized for the aldol condensation of cyclopentanone to produce aviation fuel precursor. The effect of activation condition on the physicochemical properties of HBC and Mg-Zr-O/HBC were evaluated, the evolution of gas component before and after activation was explored, and the catalytic performance of Mg-Zr-O/HBC in the aldol condensation of cyclopentanone for the synthesis of aviation fuel was tested. Instead of traditional KOH activation, pyrolysis gas activation was beneficial for the reduced pollution and increased calorific value of the gas, making it an environmentally friendly method. The results showed that the activation of biochar (BOC) was improved with lower pyrolysis gas flow , higher activation temperature and longer activation time. The pore structure of carbon material was significantly improved, and the specific surface area was boosted from 15.25 m 2 /g 3 to 627.61 m 2 /g 3 . Mg-Zr-O was evenly distributed on HBC, and a large number of weak and medium basic sites were found in Mg-Zr-O/HBC, which was quite favorable for the aldol condensation. In the aldol condensation of cyclopentanone, Mg-Zr-O/HBC presented the excellent production of the targeted C10+C15 condensates of 84.95 %, which was comparable to that prepared with KOH as activator. After 8 repeated runs, the yield of the targeted condensates remained at 73.33 %. In general, it provided an environmentally friendly strategy for the preparation of HBC and the high-value utilization of pyrolysis gas assisted by pyrolysis gas for the activation of BOC.
研究领域:
能源科学
·
催化化学
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环境工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）