EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
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2018
·Vol. 2018
·期 41
·4579-4585
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IF 2.507
Xiao Liu,Wei Qi,Yuefei Wang,Rongxin Su,Zhimin He
Graphical We demonstrated that UiO-66 and its derivatives possess efficiently intrinsic lipase-like activity, catalyzing ester hydrolysis, transesterification and even the esterification reaction. It's –NH 2 functionalized analogue UiO-66(NH 2 ) exhibited the highest catalytic activity due to the synergistic catalytic effect. To overcome the disadvantages of natural enzymes, artificial enzyme mimics attracted increasing attention of researchers. Metal-organic frameworks (MOFs) are expected as one of the most appropriate candidates for artificial enzyme mimics. In this work, we demonstrate that the zirconium-based MOF material UiO-66 and its analogues possess intrinsic lipase-like activity and can efficiently catalyze ester hydrolysis, transesterification and esterification reactions. Furthermore, the UiO-66(NH 2 ) exhibits much higher catalytic activity than that of UiO-66, which can be attributed to the synergy effect between the zirconium cluster centres and the amino moieties during the catalytic cycle.
研究领域:
生物化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY
·
2015
·Vol. 92
·期 4
·495-502
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IF 1.541
Fu Xiao-bo,Chen Jie,Song Xue-li,Zhang Yuan-ming,Zhu Yi,Yang Jun,Zhang Cheng-wu
A novel carbon solid acid catalyst was prepared by incomplete hydrothermal carbonization of β-cyclodextrin into small polycyclic aromatic carbon sheets, followed by the introduction of –SO 3 H groups via sulfonation with sulfuric acid. The physical and chemical properties of the catalyst were characterized in detail. The catalyst simultaneously catalyzed esterification and transesterification reactions to produce biodiesel from high free fatty acid (FFA) containing oils (55.2 %). For the as-prepared catalyst, 90.82 % of the oleic acid was esterified after 8 h, while the total transesterification yield of high FFA containing oils reached 79.98 % after 12 h. By contrast, the obtained catalyst showed comparable activity to biomass (such as sugar, starch, etc.)-based carbon solid acid catalyst while Amberlyst-15 resulted in significantly lower levels of conversion, demonstrating its relatively high catalytic activity for simultaneous esterification and transesterification. Moreover, as the catalyst can be regenerated, it has the potential for use in biodiesel production from oils with a high FFA content.
研究领域:
化学工程
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
FUEL
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2022
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IF 8.035
Ping Lu,Huaifang Li,Mantian Li,Jie Chen,Changshen Ye,Hongxing Wang,Ting Qiu
In this work, acidic ionic liquid (AIL) was grafted into NH 2 -UiO-66 through acid-base interaction. And the novel heterogeneous catalyst x AIL@NH 2 -UiO-66 ( x means the mass ratio of AIL to NH 2 -UiO-66) was first applied in the field of biodiesel production. The optimal catalyst 3AIL@NH 2 -UiO-66 with good wettability (with reactants) and high acidity was prepared successfully. Accordingly, the 3AIL@NH 2 -UiO-66 can be widely applied in biodiesel production from different raw materials. The conversion of free fatty acids (FFAs) in esterification was above 90%, as well as the biodiesel yield in transesterification was above 80%, showing excellent catalytic activities of 3AIL@NH 2 -UiO-66. And the 3AIL@NH 2 -UiO-66 also revealed excellent reusability, with the conversion of oleic acid decreases from 96.86% to 90.42% after 6 runs. In addition, the interaction between any two of the three factors (catalyst dosage, reaction time and molar ratio) on the oleic acid conversion was revealed with 3D response surface technology. By the mechanism investigation, the good wettability with reactants and high acidity of the catalysts are identified as key factors for biodiesel production. The method of anchoring ionic liquids with organic linkers for the application of MOFs in biodiesel production offers abundant possibilities.
研究领域:
化学工程
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催化材料
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2021
·Vol. 13
·期 19
·3417
·
IF 4.329
Xinhui Wang,Na Wang,Baoming Xu,Yili Wang,Jinyan Lang,Junliang Lu,Guorong Chen,Heng Zhang
Different modification process routes are used to improve the modified cellulose nanocrystalline (MCNC) with higher fatty acid by esterification reaction and graft polymerization to obtain certain hydrophobic properties. Two preparation methods, product structure and surface activity, are compared and explored. Experimental results show that the modified product is still at the nanometer level and basically retains the crystal structure of the raw cellulose nanocrystalline (CNC). The energy consumption of the two preparation methods is low; however, the esterification method with co-reactant requires short reaction time, and the degree of substitution of the product is high. The modified product prepared by grafting polymerization method has a high HLB value and amphiphilicity, which can effectively reduce the surface tension of water. Therefore, it can be used as a green and environmentally friendly surface-active substance.Keywords:CNC;esterification reaction;graft copolymerization;hydrophobic modification
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
World Journal of Engineering
·
2014
·Vol. 11
·期 3
·271-278
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IF 0
Leqin He,Jiquan Zhao,Shenjun Qin,Tao Chang,Yuecheng Zhang,Guangqing Zhang,Xiaorui Gao
Five halogen-free amphiphilic Brønsted acidic ionic liquids (ILs) based on 3-(N,N-dimethylalkylammonium)-propanesulphonate quaternary ammonium zwitterions andp-toluene sulphonic acid monohydrate were synthesized. The IL structures were characterized using1H NMR,13C NMR and (ESI)-MS. The IL thermal instability was characterized using TG-DSC. The ILs were used as dual-solvent catalysts for esterification of several carboxylic acids, with different alcohols under mild conditions to study relevant structure-activity relationships. Results showed that the miscibility of the acidic IL, which is affected by the length of the carbon chain in the cation, is an important factor influencing the activity of the catalyst for the esterification reaction. Post-processing steps were simple, and the catalyst could be reused easily.
研究领域:
化学
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催化科学
✓ 已验证
DOI
RSC Advances
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2017
·Vol. 7
·期 54
·33714-33725
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IF 3.108
Jianhua Li,Haiyan Liu,Tingting An,Yuanyuan Yue,Xiaojun Bao
This article describes a novel method to dealuminate and realuminate H-beta zeolites as catalysts for removing organic acids from bio-oils via their esterification reactions with alcohols. Modified H-beta zeolites were prepared by leaching with solutions of oxalic acid, DL-malic acid, and DL-tartaric acid that have different numbers of hydroxyl groups. The results showed that, while all three organic acids can dealuminate the parent H-beta zeolite, with Al(VI)a atoms and Al(IV)c ones being preferentially removed, they show quite different realumination abilities, with tartaric acid with two hydroxyl groups having the highest realumination ability. The concomitance of dealumination and realumination and their dependence on the hydroxyl group numbers of the organic acids provide the possibility of finely tuning the Al and acidity distributions of the resulting zeolites. Among the three acid treated H-beta zeolites, the one obtained from malic acid leaching exhibited the best performance in catalyzing the esterification reaction between acetic acid and sec-butyl alcohol, attributed to its suitable quantity and density of medium and strong Brönsted acid sites and enhanced aluminum gradient. The catalytic results obtained in a fixed-bed microreactor revealed that the malic acid leached H-beta exhibited dramatically enhanced catalytic performance compared to the commercial ion-exchange resin Amberlyst® 15, demonstrating great potential for industrial application.
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
FUEL
·
2023
·
IF 7.4
Yibo Zhang,Wei Wang,Chunlai Liu,Peihang Shen,Zelong Liu,Jianglei Hu,Fengwei Shi
In this work, we successfully synthesized a novel composite (HPW@MOF-199/SBA-15C, PMS-15C) in which MOF-199 encapsulated HPW catalyst (named HPW@MOF-199) was confined in SBA-15C, which is the carboxy-functionalized SBA-15. Physicochemical properties of the composites PMS-15C were systemically characterized by N 2 adsorption–desorption isotherms, wide-angle and low-angle XRD, XPS, FT-IR, SEM, and TEM. The results exhibited that HPW@MOF-199 had been successfully synthesized and embedded into the SBA-15C pores by COOH on the surface of SBA-15C. Meanwhile, the composites PMS-15C exhibited high activity and excellent reuse properties in the esterification reaction of acetic acid and ethanol, and no evidence of aggregation, leaching, or inactivation of HPW@MOF-199 during repeated use. The good dispersion of HPW within the MOF-199 cage and the interaction between HPW@MOF-199 and SBA-15C may be responsible for the good catalytic activity as well as the high stability of PMS-15C.
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ENERGY
·
2017
·
IF 7.182
Yi-Tong Wang,Zhen Fang,Xing-Xia Yang
Biodiesel production was catalyzed by a novel magnetic carbonaceous acid (Zr-CMC-SO 3 H@3Fe-C 400 ) with both Brønsted and Lewis sites synthesized by a four-step method: (i) metal (Fe) ion chelation, (ii) calcination, (iii) metal (Zr) ion chelation and embedding, and (iv) sulfonation. It catalyzed the esterification of oleic acid with 97% biodiesel yield, transesterification of high acid value (AV) soybean oil with 95% biodiesel yield, and pretreatment of Jatropha oil with AV reduced from 17.2 to 0.7 mg KOH/g. Biodiesel yields (>90%) at 90 °C for 4 h reaction time were obtained for ten cycles by easy magnetic separation which showed potential practical applications in the field of green production. The synthesized catalyst was characterized with elemental analysis, XRD, ICP-OES, FT-IR, BET, VSM, SEM-EDX, HRTEM, TG-DSC and Boehm titration.
研究领域:
化学工程
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可再生能源
✓ 已验证
DOI
高影响因子
AICHE JOURNAL
·
2018
·Vol. 65
·期 2
·675-683
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IF 3.326
Hao Qin,Zhen Song,Qian Zeng,Hongye Cheng,Lifang Chen,Zhiwen Qi
The traditional production of long-chain organic esters like isobutyl isobutyrate (BIBE) suffers from severe problems due to the homogenous catalyst in process and complex system thermodynamics. In this work, an innovative bifunctional deep eutectic solvent (DES) is introduced, playing as both reaction catalyst and extraction solvent, to intensify the esterification process. The DES was formed by imidazole (Im) and p -toluenesulfonic acid (PTSA), which was for the first time found acid–base tunable, represented by weak basic DES [3Im:PTSA] and strong acidic DES [Im:2PTSA]. The formation mechanisms of [3Im:PTSA] and [Im:2PTSA] were illustrated by Fourier-transform infrared spectroscopy (FTIR) and COnductor-like Screening MOdel for Real Solvent (COSMO-RS) combined with the Im-PTSA phase diagram. The dual functions of the acidic [Im:2PTSA] in reactive extraction were evaluated by σ -potential analysis and esterification experiments. The high conversion, easy product separation, and good solvent reusability confirm the excellent catalytic and solvent effect of [Im:2PTSA]. © 2018 American Institute of Chemical Engineers AIChE J , 65: 675–683, 2019
研究领域:
化学工程
·
有机合成
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DOI
高影响因子
MONATSHEFTE FUR CHEMIE
·
2023
·Vol. 154
·期 10
·1189-1195
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IF 1.8
Wang Peng,Shi Huibing,Feng Baolin,Zhao Deming,Wu Haigang
The Ru-catalyzed highly selective alkoxycarbonylation of allenes with aliphatic alcohols (also as solvent) allow to produce useful α , β -unsaturated esters in good to excellent yields at 70 °C. Efficient regioselectivity could be controlled in the presence of N-ligands while the P-ligands had no influence on the conversion of substrates and the chemo/regioselectivity of target products. By involving N-ligand 4,7-dimethyl-1,10-phenanthroline in the catalytic system, α , β -unsaturated esters were obtained with high conversion and chemo/regioselectivity (conversion up to 99%, chemical selectivity up to 99%, regioselectivity of branched ester/linear ester up to 89/11). Graphical abstract
研究领域:
有机化学
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催化化学
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2021
·
IF 4.952
Zhe Dong,Yu Zhao,Jinliang Chen,Ming Chang,Xiaosan Wang,Qingzhe Jin,Xingguo Wang
Borneol esters have attracted increasing interest due to their potential application in the food industry. In this study, the extraction of d -borneol from Cinnamomum camphora chvar. borneol seed was carried out via steam distillation to gain highly purified d -borneol (99.66%). The lipase-catalyzed lipophilization of extracted d -borneol with oleic acid was performed in a solvent-free system. The influences of lipase type, substrate molar ratio, lipase loading, reaction temperature and reaction time on d -bornyl oleate yield were evaluated. Among four kinds of commercial lipases screened for their esterification efficiency, CRL (lipase from Candida rugose ) displayed the highest catalytic activity in the synthesis of d -bornyl oleate. The yield of more than 95% was obtained under the optimal conditions: substrate molar ratio 1:2 ( d -borneol/oleic acid), lipase loading 8%, reaction temperature 45 °C, reaction time 48 h. The structural identification of d -borneol and product d -bornyl oleate was performed by gas chromatography mass spectrometry (GC-MS) and proton nuclear magnetic resonance spectroscopy ( 1 H NMR). The results showed that the product was confirmed to be d -bornyl oleate and the purity of which was 97.51%. This study will pave the way for d -borneol and its esters application in food industry.
研究领域:
食品科学
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生物化学
✓ 已验证
产品关联
DOI
高影响因子
Polymer Chemistry
·
2020
·Vol. 11
·期 29
·4787-4797
·
IF 5.342
Tianqi Liu,Xin Peng,Yuanyuan Chen,Jianan Zhang,Chen Jiao,Huiliang Wang
Esterification reactions between carboxylic acids and alcohols usually occur with the assistance of a catalyst at an elevated temperature. Solid-phase esterification reactions between hydroxyl-containing polymers and small carboxylic acids without using any catalyst under ambient conditions have rarely been reported. Here, we report the occurrence of esterification reaction between poly(vinyl alcohol) (PVA) and malonic acid (MA) through a simple drying method. PVA-MA hydrogels are firstly prepared by a freezing–thawing method, and then they are dried under ambient conditions. The dried hydrogels cannot be dissolved in hot water even in the presence of a strong hydrogen bond breaking agent. Structural characterization of the PVA-MA hydrogels reveals the formation of ester bonds between the hydroxyl groups in PVA and carboxyl groups in MA. The occurrence of the esterification reaction is further confirmed by using ethylene glycol as a model compound to react with MA under ambient conditions. The strong H-bonding and chemical ester bonds formed during the drying process increase the cross-linking density of the hydrogels, and hence their mechanical properties are largely enhanced. The PVA-MA hydrogels after the drying–reswelling treatment possess excellent mechanical properties, showing high tensile strengths and moduli up to 11.19 and 10.66 MPa, respectively. When the physical cross-links in the hydrogels are broken by heating in water, the hydrogels mainly cross-linked by ester bonding show excellent elasticity and resilience. Moreover, the formation of chemical ester bonding by drying also endows the PVA-MA hydrogels with good healing ability. The esterification in the solid phase by drying provides a new strategy to introduce chemical cross-links into polymeric materials and hence endows them with enhanced mechanical properties and functional properties.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）