CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Haoru Tang,Cong Luo,Houfang Lu,Kejing Wu,Yingying Liu,Yingming Zhu,Binshen Wang,Bin Liang
As a by-product in the biodiesel industry, surplus glycerol (Gly) has attracted considerable concern. The transesterification of Gly is one of the most promising reaction pathways to convert Gly to a value-added chemical such as glycerol carbonate (GC). Currently, development of catalysts for the transesterification with high activity is underway. Herein, a readily available biocompatible sodium citrate (Na 3 -citrate) catalyst was applied for efficient production of GC through transesterification of Gly and ethylene carbonate (EC). The effects of reaction parameters such as reaction time, EC to Gly molar ratio, reaction temperature, and catalyst loading on the reaction were investigated. Under optimal conditions, 0.01 wt% of Na 3 -citrate showed high catalytic activities with a Gly conversion of > 99 %, a GC yield of > 99 %, and a high turnover frequency of 16,925 g GC ⋅g −1 Cat ⋅h −1 . Furthermore, the reaction kinetic model for transesterification was established, and the activation energy of the Na 3 -citrate catalyzed transesterification was calculated as 51.3 kJ·mol −1 . In addition, density functional theory calculations were used to unveil mechanism of the Na 3 -citrate catalyzed transesterification. It revealed that citrate anion of Na 3 -citrate could activate hydroxy of Gly via strong hydrogen bond interaction, thereby efficiently promoting transesterification by reducing energy barrier of rate-determining step.
研究领域:
化学工程
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催化科学
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可再生资源转化
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DOI
高影响因子
Polymer Chemistry
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2024
·
IF 4.1
Quan Yan,Bailiang Xue,Tonghe Zhang,Wenliang Wang,Xinping Li,Xiaojun Shen,Lulu Ning,Xianzhi Meng,Wei Zhao
The star–star coupling is often regarded as an undesirable side reaction in in the synthesis of star polymers. To mitigate this issue, strategies such as operating at low temperatures, maintaining low monomer concentrations, and limiting monomer conversion are typically employed, albeit at the cost of reduced synthetic efficiency in producing the desired polymer materials. In this study, we propose a novel approach to harness this side reaction for the creation of a lignin-containing, sustainable, and solvent-resistant dynamic dual network using a one-pot synthesis strategy. Initially, a lignin-based macroinitiator with low polydispersity index (PDI) was synthesized to facilitate the precise formation of well-defined star polymers functionalized with epoxy groups. Subsequent to this, the first network, composed of star-shaped lignin-grafted copolymers, was successfully established through the utilization of the free radical bimolecular termination reaction. Following this, the second dynamic crosslinked network was formed via vitrimer chemistry between epoxy and carboxylic acid. The resulting dynamic dual network, accessible through a straightforward one-pot method, exhibited excellent reprocessability and solvent resistance, rendering it suitable for applications as high-performance adhesives. This study introduces a novel strategy for the synthesis of dynamic dual networks based on star-shaped lignin-grafted copolymers, offering promising prospects for the advancement of sustainable biomaterial synthesis.
研究领域:
材料科学
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可持续化学
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2024
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IF 2.7
Shujun Zhao,Jiehao Qu,Shengjiong Yin,Xiangdong Liu,Hu Zhu
Constructing self-repairing epoxy materials based on transesterification chemistry can be regarded as a potential path for practical industrial applications given on its simplicity and ease of processing. However, there is still a challenge to improve the slow bonding exchange process for desired healing performances. Herein, this work reports a simple and effective strategy to prepare high-biomass-content self-repairing epoxy materials by introducing polyester oligomer (PEO) dicarboxylic acid as modifier into epoxidized soybean oil and itaconic acid compounds. The PEO is synthesized from glutaric anhydride and 1,4-cyclohexanediol, as well possess a unique pentamer molecular structure. It not only endows the epoxy system with improved molecular mobility in virtue of its long-chain structure, but also increases the number the essential ester groups of transesterification process, thus synergistically promoting bonding exchange rate for expected properties. As a result, the employment of PEO decreases the activation energy from 100 to 70 KJ/mol, as well as presents optimized self-repairing efficiency in storage modulus and tensile strength tests compared to the control group. It may provide a new and practical way to fabricate high-effective self-repairing epoxy system for industrial applications.
研究领域:
材料科学
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聚合物化学
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自愈材料
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环氧树脂
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可持续材料
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产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2021
·Vol. 133
·期 1
·191-208
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IF 2.081
Wang Jianye,Liu Haifeng,Chen Zhonghui,Sun Yifeng,Wang Song
Waste crayfish shell powder was utilized to prepare a series of solid base catalyst for the transesterification of glycerol with dimethyl carbonate to synthesize glycerol carbonate. Thermal decomposition behavior of waste crayfish shell powder was investigated by thermogravimetric analysis (TGA) and the different catalysts prepared at different calcinations temperature were characterized using FESEM, XRD, FTIR, BET techniques. It was clearly confirmed that the catalyst generated by the calcination of waste crayfish shell at 800 °C exhibited excellent catalytic activity, 98.7% glycerol conversion and 95.3% glycerol carbonate yield were obtained under mild reaction conditions such as 90 min of reaction time, 1:6 molar ratio of glycerol to dimethyl carbonate, 4 wt% of catalyst loading and 75 °C of reaction temperature.
研究领域:
化学工程
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催化
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绿色化学
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材料科学
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产品关联
DOI
高影响因子
Scientific Reports
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2020
·Vol. 10
·期 1
·1-14
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IF 3.998
Liu Guanhao,Yang Jingyi,Xu Xinru
The mixed metal oxides S-CaMgAl MO prepared by acidolysis, coprecipitation and calcination under different temperatures from S95 steel slag of Shanghai Baosteel Co., Ltd. were used to catalyze the transesterification of dimethyl carbonate (DMC) and glycerol for synthesizing glycerol carbonate (GC). The catalysts were characterized by EDS, XRD, FT-IR, SEM, CO 2 -TPD and nitrogen adsorption–desorption isotherms. S-CaMgAl MO calcined at 600 °C had excellent catalytic performance due to the large pore size and proper alkalinity. The effects of reaction temperature, reaction time and the amount of catalyst on transesterification were investigated to obtain the optimal reaction conditions. The glycerol carbonate yield reached 96.2% and the glycerol conversion was 98.3% under the condition of 3 wt% catalyst, 1:3 molar ratio of glycerol and DMC, 75 °C reaction temperature and 90 min reaction time. In addition, the GC yield and glycerol conversion still achieved above 90% after five cycles of S-CaMgAl MO.
研究领域:
化学工程
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环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
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2019
·Vol. 43
·期 43
·16981-16989
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IF 3.069
Bingying Jia,Miaojiang Wu,Hua Zhang,Yi Zeng,Gongying Wang
Titanates are frequently used as precursors to prepare transesterification catalysts with TiIV species. Unfortunately, it is challenging to control the dispersity of TiIV active sites on supports. Herein, a series of TiIV species is anchored on abundant linker vacancy sites by introducing point and large scale defects in UiO-66(Zr/Ti) with hierarchical-pore structure. The catalyst functionalized by titanium(IV) oxide bis(2,4-pentanedionate) shows excellent catalytic performance in the transesterification of dimethyl carbonate with phenyl acetate. The catalysts are characterized by XRD, FT-IR, N2 adsorption–desorption, XPS, SEM and STEM-HAADF techniques. The results demonstrate that the delicate mesopores in the support can not only exhibit a large surface area for the distribution of the active sites, but also provide better mass transfer performance. Meanwhile, the introduction of octahedral TiIV ions raises the activity of the catalyst via more coordinatively unsaturated ZrIV sites. Furthermore, using titanium(IV) oxide bis(2,4-pentanedionate) as a Ti source can effectively prevent the condensation of tetrahedral TiIV species anchored on the hierarchical-pore UiO-66(Zr/Ti) support.
研究领域:
催化
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材料科学
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化学工程
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2019
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IF 6.97
Zhe Dong,Zengshe Liu,Jie Shi,Hu Tang,Xia Xiang,Fenghong Huang,Mingming Zheng
A sustainable and efficient reaction system for enzymatic oil modification is imperative for the food industry. Given the interfacial activation effect of lipase, the sufficient oil–water interface is vital for excellent catalytic activity of lipase. In the present study, a Pickering emulsion reaction system was prepared through directly using reactants as the oil phase and stabilized by mesoporous carbon spheres (MCS) after immobilization of lipase AYS (Candida rugosa, lipase@MCS). Lipase@MCS worked as both the emulsifier and catalyst. Each droplet in the Pickering emulsion was regarded as a microreactor with the reactants in the oil phase, and the removal of the product H2O “pushed” the reaction forward. Taking advantage of the adequate oil–water interface for “lid” opening of lipase and rapid mass transfer in MCS, the Pickering emulsion exhibited excellent enzymatic activity toward phytosterol esterification and transesterification, achieving 95.0% conversion after 1.5 h and catalytic efficiency (CE) of 6.8 mmol g–1 h–1 under nonequilibrium conditions. It is the best performance reported currently with the shortest reaction time, minimal amount of catalyst, and the highest CE (19-fold higher than free lipase one-phase reaction system). Immobilization of lipase on the MCS not only endowed the lipase with exceptional recyclability but also afforded a shield to protect the enzyme from deactivation in a harsh environment, as evidenced by the thermotolerance and recycling test results. This paper paves the way to advancing progress in enzyme-immobilized Pickering emulsion as a sustainable and high-efficiency platform for biocatalysis application.
研究领域:
生物化学
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食品科学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
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2014
·Vol. 52
·期 20
·2998-3003
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IF 3.245
Jinbao Xu,Weizhen Lian,Stergios Pispas,Guangzhao Zhang
A facile one-pot 1,8-diazacyclo-[5,4,0]undec-7-ene (DBU) catalyzed transesterification/atom transfer radical polymerization (ATRP) strategy has been successfully developed through the combination of copper/DBU-catalyzed ATRP and DBU-catalyzed transesterification reactions. Well-defined poly(methacrylate)s with various side ester groups have been synthesized by ATRP and transesterification of acyl donor 2,2,2-trifluoethyl methacrylate with various alcohols, such as benzyl alcohol, n -butanol, iso -propyl alcohol, methanol, triethylene glycol monomethyl ether, propargyl alcohol, and 6-azido-1-hexanol by the one-pot process. Kinetic studies indicate that the ATRP process proceeded in a controllable manner without the interference of the transesterification reactions. Expansion of the binary system to a higher level ternary system has been successfully achieved by the combination of copper(I)-catalyzed azide–alkyne cycloaddition, transesterification, and ATRP reactions. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52 , 2998–3003
研究领域:
高分子化学
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材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2017
·
IF 3.671
Chenyu Jiang,Chuanchuan Cheng,Mei Hao,Hongbin Wang,Ziying Wang,Cai Shen,Ling-Zhi Cheong
Eggshell membrane (ESM) is an industrial waste that is available in abundance from food industry. Present study investigated the physicochemical properties of oxidized ESM and compared the efficiency of ESM and oxidized ESM as carrier for Burkholderia cepacia lipase (BCL) used in esters hydrolysis and transesterification . Following oxidation treatment, FTIR analysis and Ellman’s assay showed amino acid cysteine in ESM was oxidized to form disulfide bond-containing cystine . In addition, AFM analysis showed ESM which exhibited a highly porous filamentous structure appeared to be coalesce following oxidation treatment. Oxidized ESM also showed reduced porosity (38.67%) in comparison to native ESM (51.65%). BCL were successfully immobilized on oxidized ESM through carrier activation method (enzyme loading of 5.01 mg protein/g oxidized ESM). These immobilized lipase demonstrated significantly (P < 0.05) enhanced catalytic stability with close to 100% of initial hydrolysis (12.03 ± 0.29 mmol/min/g) activity; and more than 85% of its initial transesterification (7.83 ± 0.05) activity for at least 10 consecutive runs. Enhanced catalytic stability of BCL immobilized on oxidized ESM might be due to stabilization of the protein structure in oxidized ESM by disulfide bonds which helped formation of a stable bonding with BCL.
研究领域:
生物化学
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酶工程
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
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2017
·Vol. 19
·期 8
·1-11
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IF 2.02
Cheong Ling-Zhi,Wei Yayu,Wang Hongbin,Wang Zhiying,Su Xiurong,Shen Cai
Zeolitic imidazolate frameworks (ZIF) represent one of the metal organic frameworks (MOF) with high potential for enzyme immobilization due to their exceptional chemical and thermal stability, negligible cytotoxicity, and easy synthesis under mild biocompatible conditions. Amine-functionalized ZIF-8 (An-ZIF-8) are capable of forming multipoint attachment via hydrogen bonding with lipase which will immobilize and further enhance stabilization of lipase. In addition, increased hydrophilicity of An-ZIF-8 will increase partitioning of An-ZIF-8 immobilized lipase at the aqueous/organic interface which enable lipase to expose its active site and retain its catalytic activity at its highest. Present study reports the use of ZIF-8 and An-ZIF-8 nanoparticles as carrier for Burkholderia cepacia lipase (BCL), compares the ester hydrolysis and transesterification activities of immobilized lipase with those of free lipase, and evaluates the reusability and recovery rate of the immobilized lipase. An-ZIF-8 nanoparticles (average 130.42 ± 0.55 nm) were facilely synthesized via mixing ZIF-8 nanoparticles with ammonia hydroxide solution. Despite having similar characteristics of high crystallinity and forming cuboid-like particles, An-ZIF-8 demonstrated significantly ( P < 0.05) lower Brunauer-Emmett-Teller (BET) surface area and higher thermal stability than ZIF-8. BCL were successfully immobilized on ZIF-8 (BCL@ZIF-8) and An-ZIF-8 (BCL@An-ZIF-8) nanoparticles with an average lipase loading rate of ~ 8 mg/g MOF. The immobilized BCL demonstrated no significant differences in terms of esters hydrolysis and transesterification activities with those of free BCL. BCL@An-ZIF-8 demonstrated superior catalytic stability in comparison to BCL@ZIF-8 with retainment of more than 80% of its initial hydrolysis and transesterification activity for at least 10 repeated runs. In addition, more than 80% of the BCL@An-ZIF-8 can be easily recovered during each cycle of the reusability test through simple centrifugation.
研究领域:
生物化学
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材料科学
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酶工程
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产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2021
·Vol. 139
·期 11
·51779
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IF 3.125
Yue Yin,Linghui Meng
In the present study, an investigation was conducted on the effects of polyhedral oligomeric silsesquioxane (POSS) on the mechanical, morphological, and thermal properties of PET-based nanocomposites. When the epoxy groups reacted with the PET end groups, the transesterification catalyst zinc acetylacetonate was introduced to facilitate the reaction between PET matrix and EPOSS. As clearly observed in the SEM image, 3 wt% POSS was added to PET matrix, the size of POSS particles was lower than 50 nm. As revealed from the EDX spectrum, the silicon signal was located in the EPOSS agglomerated particles and exhibited an even distribution in the entire PET matrix, which demonstrated a unique dispersion. Furthermore, it was reported that EPOSS exhibited nucleating agent performance, which suggested the higher temperature for melting crystallization (Up to 205.6°C while neat PET only reached 194.3°C). On the whole, EPOSS was revealed to act as a nucleating agent, whereas it could significantly facilitate the crystallization of PET by expediting the nucleation. Moreover, it could, to a certain extent, improve the mechanical properties of PET. These findings were attributable to the fact that PET and EPOSS exert a more comprehensive interface effect and a higher dispersion effect through the transesterification reaction.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
ChemistrySelect
·
2023
·Vol. 8
·期 8
·e202203952
·
IF 2.1
Pinmei Yan,Xin Zhang,Yuanyuan Huang,Gengwei Liu,Peng Liu,Chenjie Li,Pengbin Pan,Yuangen Yao
Graphical After desilication, the catalyst structure remained unchanged, the pore size increased, the number of mesoporous pores increased, the specific surface area increased, the alkalinity increases, and the strong acid site disappears. After oxides loading, medium strong alkalinity and medium strong acidity increased further. The higher the base strength, the higher the negative charge on EtO δ− , to facilitate the reaction. Ethyl methyl carbonate (EMC) is the product of the partial transesterification of dimethyl carbonate (DMC) with ethanol (EtOH). How to modulate the catalyst with suitable acidity and alkalinity is of key importance for achieving both high activity and selectivity toward EMC. Herein, an Mg−Zn−P/AT-ZSM-5 catalyst with moderate basicity and moderate acidity was intelligently designed by the co-doping of Mg−Zn−P after the desilication of ZSM-5. Under the optimized reaction conditions, the EtOH conversion can reach 99.1 % with a high EMC selectivity of 96.3 %. Based on the results of multiple characterizations, the enhanced EtOH conversion and high EMC selectivity should be attributed to the well dispersed supported metal species, and enhanced metal-support interactions, especially the suitable surface acidity and alkalinity property of the catalyst. Such work provides a more reasonable design strategy for the preparation of a catalyst used for the transesterification reaction of DMC and EtOH to selectively produce high-valued EMC.
研究领域:
化学工程
·
催化反应
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）