ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Man Yang,Yuxiang Jiao,Jianglin Duan,Keying Wu,Hailiang Song,Shaodong Sun,Yujing Ren
Taking the background of the ambiguous role of oxophilic metal oxide in metal-acid bifunctional catalysts for the important field of tetrahydrofurfuryl alcohol (THFA) hydrogenolysis, a linear relationship between the W═O/W–OH content in sub-nano-Rh-supported WOx and 1,5-pentanediol (1,5-PeD) yields from THFA hydrogenolysis has been established. It reveals that the higher reduction temperature promotes the surface Rh/W ratio. Thus, hydrogen spillover is facilitated, leading to more surface W═O structures and thereby more in-situ-reduced W–OH generation. W–OH structures work as the active sites to provide in situ Brønsted acid, resulting in enhanced selective activation for secondary C–O bonds of THFA. This discovery reveals the unique role of the surface structure on oxophilic metal oxide in chemoselective hydrogenolysis of the secondary C–O bond in polyols.
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
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 49
·期 3
·746-754
·
IF 2.7
Bing Fang,Haiyue Wang,Wei Chang,Yibang Yao,Liying Guo,Yuanyuan Zhao,Bing Liu
The utilization of aliphatic diols as a substitute for epoxides in the reaction with CO2 to produce cyclic carbonates offers a cost-effective and less hazardous synthesis route. This approach aligns with green chemistry principles and presents new strategies to combat climate change. This study primarily focuses on the innovative application of an alkaline ionic liquid in conjunction with a Brønsted acid for the catalytic synthesis of cyclic carbonates from CO2 and aliphatic diols. Three alkaline ionic liquid catalysts [DBUH]PHY, [TBDH]PHY, and [DBUH]TBD were successfully synthesized using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), and phenol as precursors. Their chemical structures and thermal properties were systematically characterized using Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR), carbon nuclear magnetic resonance (13C-NMR), and thermogravimetric (TG) analysis. The catalytic performance of the three alkaline ionic liquids combined with various Brønsted acids (including sulfuric acid, phosphoric acid, and acetic acid) for the synthesis of ethylene carbonate (EC) from ethylene glycol (EG) and CO2 was investigated. The results demonstrated that the combination of [DBUH]PHY with sulfuric acid (H2SO4) exhibited the best synergetic catalytic effect. Subsequently, the process parameters were optimized to study the effects of reaction temperature, pressure, time, and catalyst loading on catalytic performance. Under optimized conditions, the catalytic efficiency of [DBUH]PHY and sulfuric acid in the synthesis of cyclic carbonates from different aliphatic diols, including ethylene glycol, propylene glycol (1,2- and 1,3-), and butanediol (1,4-), was explored. This study successfully achieved the activation of aliphatic diols and CO2 through cooperative catalysis of alkaline ionic liquids and Brønsted acids, providing an innovative catalytic system for research in this field.
研究领域:
化学
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环境科学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2024
·
IF 3.5
Zhengyan Wang,Chenhao Yuan,Dong Yang,Mifen Cui,Jihai Tang,Zhuxiu Zhang,Xu Qiao
It is of great significance to develop catalysts for the degradation of hexachlorobenzene from the industrial thermal process. In this paper, formic acid was used as a modulator to generate defect sites in Ce/Zr-UiO-66 with intrinsic Brønsted acidity. The defective formate ligands were removed through methanol–water vapor treatment to expose additional open metal sites with Lewis acidity. The intrinsic Brønsted acid sites of the resulting Ce/Zr-UiO-66-FA-P achieved a hexachlorobenzene degradation efficiency of 99.5% at 250 °C. The generated Lewis acid sites facilitated the C–C cleavage of degradation intermediates. More than 95.0% of the final products were CO2/CO, coupled with chlorinated alkanes/alkenes, which outperformed other benchmark metal oxide catalysts. The Ce/Zr-UiO-66-FA-P catalyst maintained its catalytic activity in the model industrial flue gas and humid environment. The degradation pathway of hexachlorobenzene was tracked using in situ FT-IR spectra.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemSusChem
·
2019
·Vol. 12
·期 22
·4927-4935
·
IF 7.804
Xiao-ling Qu,Min Jiang,Bing Wang,Jin Deng,Rui Wang,Qiang Zhang,Guang-yuan Zhou,Jun Tang
Graphical Low loading : With a small catalyst loading of metal-free and selective ionic liquids (0.1 % based on 2,5-furandicarboxylic acid), bioderived poly(ethylene 2,5-furandicarboxylate) is efficiently prepared with high molecular weight by the electrophilic activation induced by hydrogen bonds, which are formed between the ionic liquid [C 2 MIM] + and the carbonyl oxygen. Green synthesis of bioderived high-molecular-weight poly(ethylene 2,5-furandicarboxylate) (PEF) over metal-free catalysts is a significant challenge. This study focuses on PEF prepared from ethylene glycol and 2,5-furandicarboxylic acid (FDCA) through a direct esterification method with ecofriendly metal-free ionic liquids (ILs) as catalysts. The catalytic activities of a series of imidazolium cations in the presence of various anions are systematically investigated and found to be mainly governed by the anions. Among the ILs studied, 1-ethyl-3-methylimidazolium tetrafluoroborate ([C 2 MIM]BF 4 ) is identified as the best catalyst, showing excellent catalytic activity, selectivity, and stability, even at low catalyst loadings (0.1 mol % w.r.t. FDCA). Optimization of the polymerization parameters enables [C 2 MIM]BF 4 -catalyzed production of PEF with a high number-average molecular weight ( M n =5.25×10 4 g mol −1 ). The relationship between Brønsted acidity and catalytic activity is also investigated and the results show that the trend in catalytic activity is in good agreement with that in Brønsted acidity, as determined by the Hammett method. Additionally, on the basis of experimental results and density functional theory calculations, an electrophilic activation mechanism induced by hydrogen bonds is proposed. This strategy of adjustable acidity and anion structure in ILs provides an opportunity to develop other ILs for bio-based polyesters through green synthesis pathways.
研究领域:
化学工程
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材料科学
·
绿色化学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2019
·Vol. 11
·期 16
·3903-3912
·
IF 4.495
Nian Lei,Xiaochen Zhao,Baolin Hou,Man Yang,Maoxiang Zhou,Fei Liu,Aiqin Wang,Tao Zhang
Graphical Pt at it, again ! The highest 1,3-PDO yield was obtained over the Pt/WO x /Al 2 O 3 catalyst with a medium domain size of WO x and a Pt/W atomic ratio of 1/4∼1/2, which favored the dispersion of Pt and maximized the number of Pt−WO x interface sites, and consequently promoted the in-situ production of strong Brønsted acid sites. Selective cleavage of secondary C−O bond is an important yet challenging strategy in glycerol valorization, and the product 1,3-propanediol (1,3-PDO) is of great value in polyester industry. Herein, we report a series of Pt/WO x /Al 2 O 3 catalysts for selective hydrogenolysis of glycerol in a fixed-bed reactor and obtain the highest space-time yield of 1,3-PDO (191.7*10 −3 g 1,3-PDO h −1 g −1 cat. ) to date. Both Pt and W have substantial effects on the 1,3-PDO yield with the optimum Pt/W atomic ratio of 1/2∼1/4. Spectroscopy characterizations as well as chemisorption experiments reveal that at the medium domain size of WO x , hydrogen spillover can take place to the greatest extent due to the improved dispersion of Pt and the suitable reducibility of WO x . Dehydration/dehydrogenation tests of 2-butanol suggest that strong Brønsted acid sites are created via hydrogen dissociation at the Pt−WO x interface and spillover to the neighboring oxygen atom. Such in situ formed protons are critical to the selective cleavage of secondary C−O bonds of polyols.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
IF 16.683
Shangchao Xiong,Jianjun Chen,Nan Huang,Tao Yan,Yue Peng,Junhua Li
The degradation of catalyst properties, rather than the deposition of NH 4 Cl, was the main reason for the deactivation of the MnCe low-temperature SCR (selective catalytic reduction) catalyst under HCl atmosphere. Cl ions prefer to be located at the oxygen vacancies around Mn cations on the MnCe surface. The adsorbed Cl ions could further promote the formation of oxygen vacancies. Therefore, the active Mn sites on the surface of MnCe would be quickly covered by Cl ions when HCl was present and thus promote the formation of Brønsted acid sites. However, the ionic NH 4 + adsorbed on the Brønsted acid sites of MnCe and MnCe − Cl were not fully utilized in the SCR reaction. Meanwhile, the reactivity of the coordinated NH 3 bonded with Lewis acid sites was significantly restrained by HCl due to the significant inhibition of the redox performance. Overall, HCl could obviously restrain the low-temperature SCR activity of MnCe.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 66
·41546-41551
·
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
·
催化反应
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 16
·12782-12787
·
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
·
催化化学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2024
·
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
✓ 已验证
DOI
高影响因子
Energy Technology
·
2015
·Vol. 4
·期 5
·600-609
·
IF 2.824
Yating Shen,Yunlei Zhang,Yao Chen,Yongsheng Yan,Jianming Pan,Meng Liu,Weidong Shi
Stable oil-in-water high internal phase emulsions (HIPEs) with an internal phase volume fraction of 85 % were stabilized using Tween 85. The prepared poly(HIPEs) were first investigated as adsorbents to treat water polluted with Cr III , and then the catalysts with Lewis acidic sites was synthesized. The catalysts with Brønsted acidic sites were obtained by ion-exchanging. The as-prepared HIPEs–Cr III (PEs–Cr III ) and HIPEs–SO 3 H (PEs–SO 3 H) possess open-cell structure, interconnecting pores, and strong acidity, they are utilized as highly efficient catalysts for the conversion of biomass to 5-hydroxymethylfurfural (HMF). These results showed maximum production yields for cellulose, glucose, and fructose of 37.0 %, 58.0 %, and 80.8 %, respectively. PEs–Cr III and PEs–SO 3 H can be very easily recycled at least four times without significant loss of activity. Herein, a new method is presented to transform cellulose by using two catalysts in a one-pot process for meeting the varying demands involved at different reaction stages.
研究领域:
化学工程
·
生物质能
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 8
·2578-2588
·
IF 6.177
Leilei Zhou,Weiwei Lin,Xinchao Wang,Zhuangqing Wang,Yinze Yang,Liyan Zhang,Haiyang Cheng,Masahiko Arai,Fengyu Zhao
The production of biofuels (hydrocarbons) from renewable biomass resources has attracted much attention in the fields of green energy and sustainable chemistry. Herein, catalytic hydrodeoxygenation of methyl laurate (n-C11H23COOCH3) to produce hydrocarbons n-C12H26 and n-C11H24 has been investigated over Ru dispersed on acidic supports H-ZSM-5, Al2O3 and SiO2, and the reaction rate and the product distribution were discussed and correlated with surface Brønsted and Lewis acid sites and active Ru species in detail. The reaction rate at the initial stage increased with the amount of the total acid sites, and the ratio of n-C12H26/n-C11H24 and the selectivity to n-C12H26 were positively correlated with the amount of Brønsted acid sites. The Ru active species presented to be more electron-deficient on the catalysts with a larger amount of Brønsted acid sites on which an η1-(O) adsorption configuration of 1-C11H23CHO was confirmed, which favoured the formation of n-C12H26, thus varying the product distribution. Besides, Brønsted acid sites could provide protons to promote the hydrogenolysis of n-C11H23COOCH3 and the following dehydration to produce n-C12H26.
研究领域:
绿色能源
·
催化化学
·
可持续化学
✓ 已验证
产品关联
DOI
高影响因子
TETRAHEDRON LETTERS
·
2022
·
IF 2.032
Xiangshan Li,Shihao Liu,Yao Chen,Guangxu Zhang
A novel Brønsted acidic heteropolyanion-based ionic liquid (IL) ([MIMPS] 3 PW 12 O 40 ) was synthesized and employed to catalyze the Baeyer-Villiger (BV) reaction to produce ε-Caprolactone (ε-CL). Noteblely, the prepared IL catalyst exhibited higher catalytic activity compared to solid acid catalysts duo to its behavior of reaction-induced self-separation. It meaned that the IL catalyst could switch from solid to liquid, then back to solid state during the reaction, which broke the limit of the constant heterogeneous state of the catalyst in the reaction system. The characterization results of FT-IR, 1 H NMR, XRD, and XPS indicated that the phosphotungstic anion (PW 12 O 40 3- ) was successfully modified by the organic precursor MIMPS . And TG-DTA and Py-IR results illustrated that the catalyst possessed good thermal stability and Brønsted acidity. Furthermore, the activity evaluation experiment of the catalyst confirmed that the introduced SO 3 H group of the cation part and the active component tungsten of the anion part were the key to the activity of the IL catalyst. More importantly, the synergistic effect between SO 3 H group and the active component tungstencatalyst leading to a superior catalytic performance such as cyclohexanone conversion attained 93.51 % and the yield and selectivity of ε-CL that were up to 93.26 % and 99.73 % under the optimum conditions. Finally, the kinetic process of the BV reaction was appropriately described by the second-order reversible reaction kinetics model and the calculated results were also in good agreement with the experimental datas.
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
危险品化学品经营许可证（带存储）