RSC Advances
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2017
·Vol. 7
·期 66
·41546-41551
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IF 3.108
Haosheng Xin,Tingwei Zhang,Wenzhi Li,Mingxue Su,Song Li,Qun Shao,Longlong Ma
In this work, glucose was transformed into 5-hydroxymethylfurfural (HMF) and 5-ethoxymethylfurfural (EMF) in the presence of AlCl3·6H2O and a Brønsted solid acid catalyst (PTSA–POM). GVL (γ-valerolactone)–water and ethanol–water solvent systems were evaluated in the dehydration reaction of glucose into HMF and EMF, respectively. Water content and dosage of AlCl3·6H2O were examined in the conversion of glucose into HMF, and some valuable chlorides (FeCl3·6H2O, NiCl2·6H2O, CrCl3·6H2O etc.) were also used in contrast with AlCl3·6H2O. Some different organic solvents were added to the ethanol–water system to explore whether it would be beneficial to the generation of EMF. A high yield of HMF (60.7%) was obtained at 140 °C within 60 min in GVL–water (10 : 1) solvent system, and total yield 42.1% of EMF and HMF (30.6% EMF, 11.5% HMF) was achieved at 150 °C after 30 min in an ethanol–water (9 : 1) solvent system.
研究领域:
化学工程
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催化反应
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高影响因子
RSC Advances
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2014
·Vol. 4
·期 43
·22669-22677
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IF 3.708
Zhongkui Zhao,Hongling Yang,Yu Li
This work presents a facile approach for clean and chemoselective synthesis of various functionalized arylamines from their corresponding substituted nitroarenes through the unexpected synergistic effect of a Lewis acid and the Ni–W2C/AC catalyst, affording almost 100% arylamine yield. The results challenge the long-held axiom that the combination of Lewis acid and hydrogenation catalyst mainly enhances the transformation of nitrobenzene (NB) to p-aminophenol via Bamberger rearrangement of the formed intermediate phenylhydroxylamine (PHA) under catalytic hydrogenation conditions. X-ray diffraction (XRD) and FT-IR spectroscopy were employed to reveal the relationship between catalyst nature and catalytic performance, and a plausible reaction mechanism is also proposed. Reaction results demonstrate that the FeCl3–Ni–W2C/AC catalytic system shows comparable catalytic performance towards precious metals for chemoselective reduction of various aromatic nitro compounds, affording 100% yield for all substrates involved in this work (99.5% of isolated yield for model substrate). Moreover, it can be found that the catalyst could be easily recovered by filtration and recycled without visible loss of its catalytic activity. Therefore, the developed FeCl3–Ni–W2C/AC catalytic system in this work can be considered as a practical candidate for clean and highly-efficient synthesis of diverse functionalized arylamines. We believe this approach can be extended to the other hydrogenation reactions.
研究领域:
化学
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催化科学
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DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2023
·
IF 9.9
Haifan Wang,Menglei Yuan,Jingxian Zhang,Yiling Bai,Ke Zhang,Bin Li,Guangjin Zhang
Ammonia (NH 3 ) synthesis at mild conditions by electrocatalytic nitrogen reduction (eNRR) has received more attention and has been regarded as a promising alternative to the traditional Haber–Bosch process. Lewis acid-base pairs (LPs) can chemisorb and react with nitrogen by electronic interaction, while the tuning of the microenvironment near electrode can hinder hydrogen evolution reaction (HER) thus improving the selectivity of the eNRR. Herein, the FeOOH nanorod coupled with LPs on the surface (i.e., Fe, Fe–O) was synthesized, which could effectively drive eNRR. Meanwhile, polyethylene glycol (PEG) was introduced to serve as a local non-aqueous electrolyte system to inhibit HER . The prepared FeOOH-150 catalyst achieved outstanding eNRR performance with an NH 3 yield rate of 118.07 μg h −1 mg cat −1 and a Faradaic efficiency of 51.4 % at −0.6 V vs. RHE in 0.1 M LiClO 4 + 20 % PEG . Both the experiment and DFT calculations revealed that the interaction of PEG with Lewis base sites could optimize nitrogen adsorption configuration and activation.
研究领域:
化学
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材料科学
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电化学
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DOI
PubMed
高影响因子
DALTON TRANSACTIONS
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2024
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IF 3.5
Peiyao Liu,Zhengzeng Yang,Mengyuan Zhang,Yufeng Liu,Dandan Han,Dan Wu,Charles Chunbao Xu,Jianshe Wang
C-H carboxylation of furoic acid (FA) with CO2 is an atom-efficient strategy to produce 2,5-furandicarboxylic acid (2,5-FDCA) from lignocellulose. The existing carbonate-promoted CO2 carboxylation processes rely on the use of large amounts of expensive Cs2CO3 as deprotonating reagent and molten salt. Substitution of Cs with other cheap and abundant alkali ions (such as K and Na) can reduce the use of Cs, but faces the problem of low yield of 2,5-FDCA. This study found that the addition of catalytic amounts of ZnCl2 as a Lewis acid can increase the yield of 2,5-FDCA in the CO2 carboxylation reaction of Na/K-FA in a molten salt reaction system. 1H NMR analysis and DFT calculations confirmed that ZnCl2 coordinates with the furan ring through electron transfer from the conjugated furan ring to Zn2+, thereby activating the H at the C5 position of Na/K-FA. This coordination lengthened the C5-H bond and lowered its heterolytic dissociation energy, making it more susceptible to being deprotonated by CO32- and subsequently carboxylated by CO2. The developed Lewis acid coordination strategy provides a new idea for the efficient construction of C-C bonds between CO2 and aromatics through carbonate-promoted C-H carboxylation.
研究领域:
化学工程
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可再生资源转化
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催化化学
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DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
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2014
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IF 3.679
Lipeng Zhou,Lin Wu,Hongji Li,Xiaomei Yang,Yunlai Su,Tiangliang Lu,Jie Xu
A facile and efficient method to improve the selectivity of methyl lactate (MLA) in the chemical conversion of glucose in methanol catalyzed by homogeneous Lewis acid was established. The yield of MLA was efficiently improved through controlling the acidity of the reaction solution by neutralization of protons generated from the hydrolysis/methanolysis of SnCl 4 . The mechanism of glucose conversion to MLA catalyzed by SnCl 4 -NaOH was explored. The effects of the concentration of catalyst and substrate and the reaction temperature and time were systematically studied. The catalyst system of SnCl 4 -NaOH can efficiently convert glucose, fructose, and sucrose to MLA with yields of 47%, 57%, and 51% at 160 °C for 2.5 h, respectively. The catalyst can be regenerated and reused at least three times in the conversion of glucose to MLA without significant loss of activity and selectivity.
研究领域:
化学工程
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催化化学
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DOI
高影响因子
RSC Advances
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2016
·Vol. 6
·期 16
·12782-12787
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IF 3.289
Ye-Min Lu,Hu Li,Jian He,Yan-Xiu Liu,Zhi-Bing Wu,De-Yu Hu,Song Yang
Partially hydroxylated AlF3 (denoted as AlF3) was synthesized by using a sol–gel method, and unambiguously characterized by FT-IR, XRD, NH3-TPD, SEM, TEM, N2 adsorption–desorption, and FTIR (pyridine-adsorption) techniques. The resulting mesoporous material (AlF3) simultaneously bearing Lewis and Brønsted acid sites was efficient for producing 5-hydroxymethylfurfural (HMF) from glucose, and an optimized HMF yield of 57.3% at a glucose conversion of 95.5% was obtained within 10 h at 140 °C. The effects of reaction temperature, time, catalyst amount, solvent and substrate type, and the amount of Brønsted/Lewis acid sites on conversion of glucose to HMF were also investigated. The existence of both Lewis and Brønsted acid sites in AlF3 was found to play a key role in glucose-to-HMF conversion.
研究领域:
化学工程
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催化化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Dongni Liu,Peng Cui,Fangfang Zhang,Hao Ren,Lilin Fang,Xiaosi Sun,Haiyan Ji,Wenshuai Zhu,Zhichang Liu
Ionic liquid is an ideal candidate in the extraction of aromatic compounds. The design and construction of ionic liquids with high extraction efficiency and selectivity towards to the specific aromatics remain crucial question. In this paper, with the aid of orthogonal array experiment, the imidazolium-based ionic liquids with long alkyl chain on the cations were determined to possess high aromatics extraction efficiency. Furthermore, the Lewis acid anion was introduced into the ionic liquid to form 1-dodecyl-3-methylimidazolium ferric chloride ([C 12 mim][FeCl 4 ]) and performed 62 % and 100 % extractant efficiency of naphthalene (NAP) and anthracene (ANT), respectively. Then the porous carbon materials (P1-1000) derived from hyper-crosslinked porous polymers (HCP) which possessed high BET surface area (1186 m 2 /g) was dispersed in [C 12 mim][FeCl 4 ] to form porous ionic liquid. The single extraction efficiency of NAP improved from 62 % to 77 %. The great single extraction efficiency was attributed to the high porosity, additional adsorption sites provided by the Lewis acid anions and the hydrophobic long alkyl chain on the cations. After three times extraction, the concentration of NAP dropped down to 0. The porous ionic liquids also showed good recycle performance. The construction of porous ionic liquids provided an efficient approach for extraction of polycyclic aromatic hydrocarbons from aliphatic hydrocarbon.
研究领域:
环境科学
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材料科学
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
·
IF 13.2
Maonan Ran,Guan Zhang
The NO 3 − electroreduction process presents a promising alternative to the Haber-Bosch method by offering dual benefits: removal of nitrates from wastewater coupled with efficient NH 3 production. Herein, Mo and S doped Fe 3 O 4 nanoplates grown on foam Fe (Mo-S-Fe 3 O 4 @FF) with electron-rich Mo δ+ state was synthesized through a facile hydrothermal approach. Notably, Mo-S-Fe 3 O 4 @FF electrode achieved a nearly fourfold enhancement in ammonium yield compared to foam Fe electrode, while also enhancing the NH 3 Faradaic efficiency. At − 1.3 V vs . Ag/AgCl in a K 2 SO 4 + KNO 3 solution, the Mo-S-Fe 3 O 4 @FF electrode attained a NH 3 Faradaic efficiency of 91.3 %. Furthermore, performance was observed to improve with increasing solution pH levels as the reaction proceeded. From both kinetic and thermodynamic perspectives, our findings demonstrate that high NH 3 production activity is characteristic of Mo-S-Fe 3 O 4 @FF—indicating significant enhancements in conversion rates from NO 3 − →NO 2 − →NH 3 . Theoretical calculation, in conjunction with experimental analyses, reveal that the co-modification of Fe 3 O 4 with Mo and S enhances electron transfer capacity during NO 3 − RR. This modification forms Lewis-acid (Fe-Mo) pairs that increase nitrate adsorption energy alongside Lewis-base (S-O) sites that attract protons, thereby improving overall NO 3 − RR activity. This report elucidates the synergistic effects of Lewis-acid and Lewis-base sites on optimizing catalytic performance for NO 3 − RR using foam Fe-based electrodes.
研究领域:
环境科学
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电催化
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材料科学
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2024
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IF 4.8
Wenfeng Hao,Peng Lu,Xiaosheng Wang,Yuxiang Liu
A simple and facile co-calcination strategy of Beta molecular sieves and cerous nitrate is proposed. Based on the results of XRD , UV–Vis, in-situ FTIR, and 29 Si MAS NMR techniques, open-site configurations of Ce(III)O 4 and Ce(IV)O 4 tetrahedrons are observed due to a large ionic radius of Ce 3+ and Ce 4+ ions. Open-site configurations result in a low ratio of BrØnsted and Lewis acid sites in HBeta-Ce-6. In the isomerization of α- pinene, a higher amount of Lewis acid sites increases the yield for camphene . BrØnsted acids are accessible for α- pinene to form limonene due to a high surface area and low coke deposition. Isomorphous incorporation of Ce 3+ occurs and a decreasing selectivity for limonene are observed using regenerated catalysts. These results indicate that co-calcination strategy protects Beta molecular sieves from thermal destruction, endows Beta molecular sieves with a higher relative crystallinity and porosity during calcination .
研究领域:
材料科学
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催化化学
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DOI
高影响因子
Journal of CO2 Utilization
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2021
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IF 7.132
Jiaxin Liang,Shuxian Ye,Wenjing Wang,Congxiao Fan,Shuanjin Wang,Dongmei Han,Wei Liu,Yan Cui,Limin Hao,Min Xiao,Yuezhong Meng
Bulk terpolymerization of carbon dioxide and phthalic anhydride with propylene oxide is successfully carried out using metal-free and economical Lewis pairs under mild conditions. A series of commercial organic bases are coupled with triethyl borane (TEB) as Lewis pairs to optimize the activity and the results show that the TEB/ bis(triphenylphosphine)iminium chloride (PPNCl) pair exhibits relatively high activity and selectivity. The impact of the molar ratio of TEB to organic bases, reaction temperature and CO 2 pressure as well as the catalyst loading on the activity and selectivity of the copolymerization are investigated. Particularly, the turnover frequency reaches 164 h −1 with a TEB/PPNCl molar ratio of 2/1 at 80 °C. To our delight, the poly(ester- co -carbonate)s with random or block structures can be simply tuned by choosing different organic bases coupled with TEB. In these cases, the resultant terpolymers with comprehensive properties can be readily synthesized. As expected, the incorporation of phthalic anhydride effectively modifies the thermal and mechanical properties of commercial poly(propylene carbonate) (PPC). Terpolymers named as PPC-P with 43 mol% aromatic polyester moieties displays a glass transition temperature ( T g ) of 47 °C, about 9 °C higher than that of commercial PPC, and gives a tensile strength higher than 37.6 MPa. To our delight, the synthesized PPC-P exhibits satisfactory degradation speed under standard composting condition compared with commercial PBAT and PPC.
研究领域:
材料科学
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化学工程
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高影响因子
NEW JOURNAL OF CHEMISTRY
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2019
·Vol. 43
·期 20
·7725-7732
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IF 3.069
Yun Hao,Ying-juan Hao,Jie Ren,Biao Wu,Xiao-jing Wang,Dishun Zhao,Fa-tang Li
In this work, N-methyl-2-pyrrolidonium (NMP) was acidized using hydrochloric acid to obtain [Hnmp]Cl first, which was then reacted with FeCl3 to prepare a series of inexpensive tunable [Hnmp]Cl·xFeCl3 (x = 0.2–2.0) ionic liquids (ILs) for the extractive and oxidative desulfurization of model oils. The Lewis acidities of these ILs were tested by the Fourier transform infrared (FT-IR) method, which indicated that when the x value of [Hnmp]Cl·xFeCl3 was above 1.0, the ILs exhibited Lewis acidity. The extraction results showed that the acidification of NMP reduced its dissolubility ability toward dibenzothiophene (DBT) and its Lewis acidity played a determining role in extractive desulfurization. In the catalytic oxidation removal process of the DBT model oil in the presence of H2O2, electron paramagnetic resonance (EPR) and scavenger experiments showed that the hydroxyl radical (˙OH) plays a key role and the superoxide anion radical (O2˙−) has a minor function. [Hnmp]Cl·1.5FeCl3 IL showed excellent recycling performance, which was due to its high dissolving capacity (23 700 ppm) for dibenzothiophene-sulfone (DBTO2).
研究领域:
化学工程
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环境科学
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DOI
高影响因子
FUEL
·
2021
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IF 6.609
Hui Niu,Dongzhi Zhao,Guoying Xie,Yanan Yuan,Wei Zhang,Chen Zhang,Cuiqing Li,Lingyan Cui
Al 2 O 3 , TiO 2 , ZrO 2 and SiO 2 were used for adsorptive dechlorination of model oil at different temperatures. The results showed that chlorine removal over the four mesoporous oxides sharply increased with increasing the temperature from 20 °C to 150 °C. GC–MS and ion chromatography analysis showed that 1-chlorooctane was converted into 1-octanol and chloride ion at the temperature higher than 120 °C, which were then adsorbed on the adsorbent. Precipitation pH had a significant impact on the dechlorination performance of Al 2 O 3 . Among various porous oxides, Al 2 O 3 -9.5 precipitated at pH 9.5 exhibited the highest dechlorination performance, over which the chlorine removal reached 99% after adsorption for 3 h at 150 °C. The characterization results indicated that various porous oxides contained only Lewis acid, and the dechlorination performance of the adsorbent basically increased with the increase of its total Lewis acid amount. The dechlorination efficiency for different organochlorine compounds followed the order: straight chain alkyl chlorides > chlorinated cycloalkanes > aromatic hydrocarbons. Al 2 O 3 -9.5 showed good regenerability, and the dechlorination performance of Al 2 O 3 -9.5 had only a slight decrease after six consecutive dechlorination-regeneration cycles, due to slight loss of its Lewis acid amount and surface area.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
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