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Reaction pathways and selectivity in the chemo-catalytic conversion of cellulose and its derivatives to ethylene glycol:A review
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作者 Yao Li Yuchun Zhang +2 位作者 Zhiyu Li Huiyan Zhang Peng Fu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期310-331,共22页
Biomass-to-ethylene glycol is an effective means to achieve high-value utilisation of cellulose but is hindered by low conversion efficiency and poor catalyst activity and stability.Glucose and cellobiose are derivati... Biomass-to-ethylene glycol is an effective means to achieve high-value utilisation of cellulose but is hindered by low conversion efficiency and poor catalyst activity and stability.Glucose and cellobiose are derivatives of cellulose conversion to ethylene glycol,and it is found that studying the reaction process of both can help to understand the reaction mechanism of cellulose.It is desirable to develop a reusable,highly active catalyst to convert cellulose into ethylene glycol.This ideal catalyst might have one or more active sites described the conversion steps above.Here,we discuss the catalyst development of celluloseto-ethylene glycol,including tungsten,tin,lanthanide,and other transition metal catalysts,and special attention is given to the reaction mechanism and kinetics for preparing ethylene glycol from cellulose,and the economic advantages of biomass-to-ethylene glycol are briefly introduced.The insights given in this review will facilitate further development of efficient catalysts,for addressing the global energy crisis and climate change related to the use of fossil fuels. 展开更多
关键词 ethylene glycol CELLULOSE Catalyst Retro-aldol condensation HYDROLYSIS Kinetics
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Sn nucleation and growth from Sn(II)dissolved in ethylene glycol:Electrochemical behavior and temperature effect
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作者 Kiem Van DO Hieu Van NGUYEN Tu Manh LE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2714-2732,共19页
Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks obs... Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks observed in voltammograms have demonstrated the capability of ethylene glycol solutions to electrodeposit Sn.The temperature-dependence of diffusion coefficient values derived from potentiodynamic and potentiostatic studies helped to determine and validate estimations of the activation energy for Sn(II)bulk diffusion.Chronoamperometric results have identified that,the suitable model to describe the early stage of Sn electrodeposition could be composed of Sn three-dimensional nucleation and diffusion-controlled growth and water reduction contributions,which was duly validated by theoretical and experimental approaches.From the model,typical kinetic parameters such as the nucleation frequency of Sn(A),number density of Sn nuclei(N_(0)),and diffusion coefficient of Sn(II)ions(D),were determined.The presence of Sn nuclei with excellent quality and their structures were verified using SEM,EDX,and XRD techniques. 展开更多
关键词 SN NUCLEATION growth ethylene glycol nucleation kinetics ELECTRODEPOSITION
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Analysis of Ethylene Glycol Degumming Process and Characterization of Hemp Fibers 被引量:2
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作者 池虹 秦智慧 +3 位作者 赵树元 刘柳 张瑞云 程隆棣 《Journal of Donghua University(English Edition)》 CAS 2023年第3期255-260,共6页
To overcome the shortcomings of traditional degumming process,an efficient and environmentally friendly ethylene glycol(EG) degumming process was adopted to degum hemp fibers.The surface morphology,chemical compositio... To overcome the shortcomings of traditional degumming process,an efficient and environmentally friendly ethylene glycol(EG) degumming process was adopted to degum hemp fibers.The surface morphology,chemical composition,chemical structures,and mechanical properties of the fiber samples were analyzed to explore the mechanism of the degumming process.It was found that the EG degumming process could be divided into the main degumming stage(heating) and the supplementary degumming stage(insulation).The removal rates of hemicellulose and lignin in the main degumming stage were 70.56% and 60.17%,respectively.In the supplementary degumming stage,9.95% hemicellulose and 25.39% lignin were removed.It is confirmed that EG can separate hemp fibers effectively with less damage,which holds great potential for the biomass fiber separation technology. 展开更多
关键词 hemp fiber degumming process ethylene glycol(EG) HEMICELLULOSE LIGNIN
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Study of Thermal,Phase Morphological and Mechanical Properties of Poly(L-lactide)-b-Poly(ethylene glycol)-b-Poly(L-lactide)/Poly(ethylene glycol)Blend Bioplastics
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作者 Yodthong Baimark Theeraphol Phromsopha 《Journal of Renewable Materials》 SCIE EI 2023年第4期1881-1894,共14页
A poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide)(PLLA-PEG-PLLA)block copolymer has great potential for use as a flexible bioplastic.Highly flexible bioplastics are required for flexible packaging applicatio... A poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide)(PLLA-PEG-PLLA)block copolymer has great potential for use as a flexible bioplastic.Highly flexible bioplastics are required for flexible packaging applications.In this work,a PEG was incorporated into block copolymer as a plasticizer by solvent casting.PLLA-PEG-PLLA/PEG blends with different blend ratios were prepared,and the plasticizing effect and miscibility of PEG in block copolymer were intensively investigated compared to PLLA/PEG blends.The results indicated that the PEG was an effective plasticizer for the block copolymer.The blending of PEG decreased glass-transition temperature and accelerated the crystallization of both the PLLA and PLLA-PEG-PLLA matrices.The PEG was completely miscible when blended with block copolymer and it improved thermal stability of the block copolymer matrix but not of the PLLA matrix.Film extensibility of PLLA-PEG-PLLA/PEG blends steadily increased as the PEG ratio increased.These non-toxic and highly flexible PLLA-PEG-PLLA/PEG bioplastics are promising candidates for several applications such as biomedical devices,tissue scaffolds and packaging materials. 展开更多
关键词 Poly(lactic acid) poly(ethylene glycol) polymer blends phase morphology thermal stability
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Preparation and Thermo-Responsive Properties of Poly(Oligo(Ethylene Glycol)Methacrylate)Copolymers with Hydroxy-Terminated Side Chain
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作者 陈杨轶 苏桐 +3 位作者 周仕航 谢晨迪 李京芝 邱夷平 《Journal of Donghua University(English Edition)》 CAS 2023年第6期610-621,共12页
Thermo-responsive random copolymers,poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-(ethylene glycol)methyl ether methacrylate)(P(EO_(2)-co-EO_(4/5)))and poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-ethylen... Thermo-responsive random copolymers,poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-(ethylene glycol)methyl ether methacrylate)(P(EO_(2)-co-EO_(4/5)))and poly(2-(2-methoxyethoxy)ethoxyethyl methacrylate-co-ethylene glycol methacrylate(P(EO2-co-EG4/5))are synthesized via atom transfer radical polymerization(ATRP).The successful synthesis and the narrow polydispersity index(PDI)of two copolymers are indicated by 1H nuclear magnetic resonance(1H-NMR)and gel permeation chromatography(GPC)analyses.The transition behaviors of polymers in the aqueous solution are demonstrated by changes in turbidity and particle sizes.The transition behavior of P(EO2-co-EG4/5)is found to be milder than that of P(EO2-co-EO4/5).Moreover,the presence of hydrogen bonds without thermo-responsive properties established by hydroxyl groups in the end-side chain of P(EO_(2)-co-EG_(4/5))hinders the dehydration at the transition temperature(TT).Attenuated total reflection Fourier transform infrared spectrometry(ATR-FTIR)analysis along with contact angle measurements reveals that both P(EO_(2)-co-EO_(4/5))and P(EO_(2)-co-EG_(4/5))films undergo phase transitions from hydrophilicity to hydrophobicity above TT.By examining the swelling and collapse behaviors of the polymer films during phase transitions,it can be concluded that the end hydroxyl groups may establish hydrogen bonds with neighboring ether groups within the films,which remain intact throughout the phase transition process due to their strong bonding interactions.This leads to an increase in steric hindrance within swollen films thereby impeding dehydration processes and inducing hysteresis during phase transitions. 展开更多
关键词 thermo-responsive property poly(oligo(ethylene glycol)methacrylate) polyethylene glycol methacrylate hydroxy-terminated side chain contact angle phase transition
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Significance of Nanoparticles Aggregation with Cattaneo-Christov Heat Flux on the Water and Ethylene Glycol Mixture Based MWCNTs-Nanofluid Flow over a Stretching Cylinder
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作者 Muhammad Ramzan Nazia Shahmir 《World Journal of Engineering and Technology》 2023年第4期1019-1029,共11页
This work aims to analyze the flow of electrically conducting MWCNTs-nanofluid over a stretching cylinder with the aggregation and non-aggregation effects of nanoparticles. The working fluid comprised a combination of... This work aims to analyze the flow of electrically conducting MWCNTs-nanofluid over a stretching cylinder with the aggregation and non-aggregation effects of nanoparticles. The working fluid comprised a combination of water and ethylene glycol, with volumetric proportions of (50:50) considered. Convective boundary constraints and modified Fourier law are implemented in heat transmission assessment. The mathematical flow model is formulated in the form of PDEs and is transformed into ODEs via similarity transformation. Numerical outcomes will be obtained with the use of the bvp4c technique and will be displayed with the help of graphs and tables. The results show that the surface drag coefficient is enhanced in the case of aggregation of nanoparticles whereas heat transfer rate is enhanced in the non-aggregation effect of nanoparticles. Furthermore, the temperature distribution enhances the increasing values of particle volume fraction in the case of aggregation effects of nanoparticles whereas temperature distribution lowers in the case of non-aggregation effect of nanoparticles. . 展开更多
关键词 MWCNTs-Nanofluid Nanoparticles Aggregation Water + ethylene glycol Mixture Cattaneo-Christov Heat Flux Stretching Cylinder
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Electrodeposition behavior of bright nickel in air and water-stable betaine·HCl-ethylene glycol ionic liquid 被引量:5
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作者 龚凯 华一新 +4 位作者 徐存英 张启波 李艳 汝娟坚 介亚菲 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2458-2465,共8页
The electrodeposition behaviors of nickel on glassy carbon(GC) and carbon steel(CS) electrodes were investigated in the14.3%-85.7%(mole fraction) betaine.HCl ethylene glycol(EG) ionic liquid using cyclic volta... The electrodeposition behaviors of nickel on glassy carbon(GC) and carbon steel(CS) electrodes were investigated in the14.3%-85.7%(mole fraction) betaine.HCl ethylene glycol(EG) ionic liquid using cyclic voltammetry and chronoamperometry.The results indicated that the reduction of Ni(Ⅱ) on CS electrode via a diffusion-controlled quasi-reversible process was much more facile and easier than that occurred on GC electrode,which followed a diffusion-controlled three-dimensional instantaneous nucleation and growth.Scanning electron microscopy was used to observe that the deposit was dense and contained fine crystallites with average size of(80±4) nm.Energy dispersive spectrometer analysis showed that the obtained deposit was metallic nickel.X-ray diffraction spectroscopy indicated that(111) plane was the most preferred crystal orientation.The nickel deposit was luminous and bright,and had good adhesion with the CS substrate. 展开更多
关键词 ELECTRODEPOSITION bright nickel nucleation mechanism betaine·HCl ethylene glycol
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Cu_2[ethyleneglycolbis(2-aminoethy)tetraacetate·2H_2O]·2H_2O:双核铜配合物的合成和晶体结构
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作者 刘立新 侯红卫 杜记民 《安阳师范学院学报》 2009年第2期89-91,共3页
乙二醇双(2-氨乙基醚)四乙酸(ethylene glycol bis(2-amino ethy)tetraacetate:EGTA)和氯化铜采用溶液蒸发方法在甲醇和水的混合溶液中成功合成双核铜配合物Cu2[EGTA.2H2O].2H2O。该晶体的结构数据是在单晶衍射仪进行收集的。通过晶体... 乙二醇双(2-氨乙基醚)四乙酸(ethylene glycol bis(2-amino ethy)tetraacetate:EGTA)和氯化铜采用溶液蒸发方法在甲醇和水的混合溶液中成功合成双核铜配合物Cu2[EGTA.2H2O].2H2O。该晶体的结构数据是在单晶衍射仪进行收集的。通过晶体结构分析,该晶体属单斜晶系,空间群为C2/c,晶胞参数如下:a=21.013(4),b=7.5503(1),c=13.577(2),β=90.877(2)°,V=2153.8(6)3。在化合物中,铜离子分别与配体的三个氧原子和一个氮原子以及一个水分子成键,采取五配位四面体构型,铜离子空间构型是畸变的四方锥。另外,游离的水分子与配体的氧原子形成氢键而构筑成超分子。 展开更多
关键词 双核铜配合物 乙二醇双(2-氨乙基醚)四乙酸(EGTA) 晶体结构
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Effect of copper loading on texture,structure and catalytic performance of Cu/SiO_2 catalyst for hydrogenation of dimethyl oxalate to ethylene glycol 被引量:14
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作者 Bo Zhang Shengguo Hui +3 位作者 Suhua Zhang Yang Ji Wei Li Dingye Fang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第5期563-570,共8页
Cu/SiO2 catalysts prepared by a convenient and efficient method using the urea hydrolysis deposition-precipitation (UHDP) technique have been proposed focusing on the effect of copper loading.The texture,structure a... Cu/SiO2 catalysts prepared by a convenient and efficient method using the urea hydrolysis deposition-precipitation (UHDP) technique have been proposed focusing on the effect of copper loading.The texture,structure and composition are systematically characterized by ICP,FTIR,N 2-physisorption,N2O chemisorption,TPR,XRD and XPS.The formation of copper phyllosilicate is observed in Cu/SiO2 catalyst by adopting UHDP method,and the amount of copper phyllosilicate is related to copper loading.It is found the structure properties and catalytic performance is profoundly affected by the amount of copper phyllosilicate.The excellent catalytic activity is attributed to the synergetic effect between Cu0 and Cu +.DMO conversion and EG selectivity are determined by the amount of Cu0 and Cu+,respectively.The proper copper loading (30 wt%) provides with the highest ratio of Cu + /Cu0,giving rise to the highest EG yield of 95% under the reaction conditions of p=2.0 MPa,T=473 K,H2/DMO=80 and LHSV=1.0h-1. 展开更多
关键词 CU/SIO2 copper loading dimethyl oxalate ethylene glycol copper phyllosilicate
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Synthesis of Nano-sized Yttria via a Sol-Gel Process Based on Hydrated Yttrium Nitrate and Ethylene Glycol and Its Catalytic Performance for Thermal Decomposition of NH_4ClO_4 被引量:11
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作者 陈伟凡 李凤生 +1 位作者 刘磊力 李永绣 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第5期543-548,共6页
Nano-sized yttria particles were synthesized via a non-aqueous sol-gel process based on hydrated yttrium nitrate and ethylene glycol. The effects of the molar ratio of ethylene glycol to yttrium ion and calcination te... Nano-sized yttria particles were synthesized via a non-aqueous sol-gel process based on hydrated yttrium nitrate and ethylene glycol. The effects of the molar ratio of ethylene glycol to yttrium ion and calcination temperature on crystallite size of the products were studied. The catalytic performance of the as-prepared yttria for the ammonium perchlorate (AP) decomposition was investigated by differential scanning calorimetry (DSC). The results indicate that the nano-sized cubic yttria particles with less than 20 nm in average crystallite size can be obtained after 2 h reflux at 70℃, dried at 90 ℃, forming xerogel, and followed by annealing of xerogel for 2 h, and that the addition of the nano-sized yttria to AP incorporates two small exothermic peaks of AP in the temperature ranges of 310 - 350 ℃ and 400 - 470 ℃ into a strong exothermic peak of AP and increases the apparent decomposition heat from 515 to over 1110 J·g^- 1. It is also clear that the temperature of AP decomposition exothermic peak decreases and the apparent decomposition heat of AP increases with the increase of the amount of nano-sized yttria. The fact that the addition of the 5 % nano-sized yttria to AP decreases the temperature of AP exothermic peak to 337.7℃ by reduction of 114.6℃ and increases the apparent decomposition heat from 515 to 1240 J·g^-1, reveals that nano-sized yttria shows strong catalytic property for AP thermal decomposition. 展开更多
关键词 nano-sized yttria ethylene glycol sol-gel ammonium perchlorate thermal decomposition catalytic property rare earths
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Selective swelling of polysulfone/poly(ethylene glycol) block copolymer towards fouling-resistant ultrafiltration membranes 被引量:5
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作者 Hao Yang Jiemei Zhou +2 位作者 Zhaogen Wang Xiansong Shi Yong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第1期98-103,共6页
Fouling resistance of ultrafiltration(UF) membranes is critical for their long-term usages in terms of stable performance, so convenient approaches to prepare fouling-resistant membranes are always anticipated. Herein... Fouling resistance of ultrafiltration(UF) membranes is critical for their long-term usages in terms of stable performance, so convenient approaches to prepare fouling-resistant membranes are always anticipated. Herein, we demonstrate the facile fabrication of antifouling polysulfone-block-poly(ethylene glycol)(PSF-b-PEG, SFEG)composite membranes. SFEG layer was coated onto macroporous supports and cavitated by immerging them in acetone/n-propanol following the mechanism of selective swelling induced pore generation. Thus-produced SFEG membranes possessed high permeance and excellent mechanical strength. Meanwhile, the structures and separation performances of the SFEG layers can be continuously tuned through simply changing swelling durations. More importantly, the hydrophilic PEG chains were spontaneously enriched onto the pore walls through swelling treatment, endowing intrinsic antifouling property to the SFEG membranes. Bovine serum albumin(BSA)/humic acid(HA) fouling tests proved the prominent fouling resistance of SFEG membranes, and the fouling resistance is expected to be long-standing because of the firm connection between PEG chains and PSF matrix by covalent bonding. 展开更多
关键词 Polysulfone-block-poly(ethylene glycol) Block copolymer Fouling resistance SELECTIVE SWELLING ULTRAFILTRATION membrane
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An Efficient and Stable Ionic Liquid System for Synthesis of Ethylene Glycol via Hydrolysis of Ethylene Carbonate 被引量:9
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作者 MENG Zhenying SUN Jian +4 位作者 WANG Jinquan ZHANG Jianxin FU Zengzeng CHENG Weiguo ZHANG Xiangping 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期962-966,共5页
An ionic liquid system of [Bmim]X/[Bmim]OH(X Cl,BF4,and PF6,) was developed for the hydroly-sis of ethylene carbonate to ethylene glycol. The important parameters,such as the variety of ionic liquids,molar ratio of [B... An ionic liquid system of [Bmim]X/[Bmim]OH(X Cl,BF4,and PF6,) was developed for the hydroly-sis of ethylene carbonate to ethylene glycol. The important parameters,such as the variety of ionic liquids,molar ratio of [Bmim]X to [Bmim]OH,amount of ionic liquid,molar ratio of water to ethylene carbonate,reaction tem-perature,pressure and reaction time,were investigated systematically. Excellent yield(>93%) and high selectivity(99.5%) of ethylene glycol were achieved. Under the optimum reaction conditions,the ionic liquid system could be reused at least five times and the selectivity of ethylene glycol remained higher than 99.5%. 展开更多
关键词 ethylene carbonate ethylene glycol HYDROLYSIS ionic liquids CATALYSIS
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Effects of cupric ions on the corrosion behavior of aluminum alloy 5A02 in ethylene glycol–water solution 被引量:4
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作者 Shu-lun Gao Mei Yu +2 位作者 Jian-hua Liu Bing Xue Song-mei Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第4期423-431,共9页
The effects of cupric ions on the corrosion behavior of aluminum alloy 5A02 in ethylene glycol–water solutions were studied by potentiodynamic polarization,electrochemical noise(EN),and complementary techniques inclu... The effects of cupric ions on the corrosion behavior of aluminum alloy 5A02 in ethylene glycol–water solutions were studied by potentiodynamic polarization,electrochemical noise(EN),and complementary techniques including scanning electron microscopy(SEM),atomic force microscopy(AFM),and X-ray photoelectron spectroscopy(XPS). A positive corrosion potential and increased corrosion current were observed due to the deposition of copper. The results demonstrate that the main corrosion type was pitting and the increasing cupric ion concentration augmented the pitting density. The pits became larger and deeper as a result of the embedment of copper into the surface of the alloy. Cupric ions were preferentially deposited at the defects around the secondary phase,leading to the formation of Al–Cu microgalvanic couples,which increased the corrosion rate. The corrosion rate gradually reached a stable value as the concentration of cupric ions was increased beyond 10 mmol/L. 展开更多
关键词 aluminum alloys metal corrosion cupric ions ethylene glycol PITTING
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Controlled delivery of ibuprofen from poly(vinyl alcohol)-poly(ethylene glycol) interpenetrating polymeric network hydrogels 被引量:4
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作者 Subhraseema Das Usharani Subuddhi 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第2期108-116,共9页
Hydrogels composed of poly(vinyl alcohol)(PVA) and poly(ethylene glycol)(PEG) were synthesized using glutaraldehyde as crosslinker and investigated for controlled delivery of the common anti-inflammatory drug, ibuprof... Hydrogels composed of poly(vinyl alcohol)(PVA) and poly(ethylene glycol)(PEG) were synthesized using glutaraldehyde as crosslinker and investigated for controlled delivery of the common anti-inflammatory drug, ibuprofen(IBF). To regulate the drug delivery, solid inclusion complexes(ICs) of IBF in β–cyclodextrin(β–CD) were prepared and added to the hydrogels. The ICs were prepared by the microwave irradiation method, which is more environmentally benign. The formation of IC was confirmed by various analytical techniques and the synthesized hydrogels were also characterized. Controlled release of drug was achieved from the hydrogels containing the ICs in comparison to the rapid release from hydrogels containing free IBF.The preliminary kinetic analysis emphasized the crucial role of β–CD in the drug release process that influences the polymer relaxation, thereby leading to prolonged release. The cytotoxicity assay validated the hydrogels as non-toxic in nature and hence can be utilized for controlled delivery of IBF. 展开更多
关键词 HYDROGELS Poly(vinyl alcohol) Poly(ethylene glycol) IBUPROFEN Controlled delivery systems
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Interface tuning of Cu+/CuO by zirconia for dimethyl oxalate hydrogenation to ethylene glycol over Cu/SiO2 catalyst 被引量:8
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作者 Yujun Zhao Huanhuan Zhang +4 位作者 Yuxi Xu Shengnian Wang Yan Xu Shengping Wang Xinbin Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第10期248-256,共9页
An efficient ZrO2-doped Cu/SiO2 catalyst was fabricated through hydrolysis precipitation method(HP)and used to produce ethylene glycol(EG)through dimethyl oxalate(DMO)hydrogenation.The states for zirconia on copper ca... An efficient ZrO2-doped Cu/SiO2 catalyst was fabricated through hydrolysis precipitation method(HP)and used to produce ethylene glycol(EG)through dimethyl oxalate(DMO)hydrogenation.The states for zirconia on copper catalyst and roles in DMO hydrogenation were investigated through various characterization tools,including N2 physical adsorption,XRD,H2-TPR,Methyl glycolate-TPD-MS,XPS,XAES as well.Compared with common ammonia evaporation and co-precipitation methods used in catalyst preparation,this HP method is found to effectively suppress the agglomeration and further size growth of copper nanoparticles by enhancing the interactions between copper and zirconia species.More importantly,uniform distribution of ZrO2 dopant is achieved due to the pseudo-homogeneous reactions in the mixing step of catalyst preparation.A proper amount of zirconium dopant helps achieve the desirable proportion of Cu+/(Cu++CuO)for surface copper species,especially promotes the production of Cu+species originated from Cu-ZrO2 species at the interface of copper and zirconia particles.In comparison with Cu+species formed from copper phyllosilicates reduction,the Cu+sites derived from Cu-ZrO2 species show higher adsorption ability of MG,an important intermediate species in ethylene glycol production.These adsorbed MG molecules further react with atomic hydrogen shifted from adjacent metallic copper surface,leading to a higher catalytic behavior.For the EG production via DMO hydrogenation,the turnover frequency(TOF)normalized by CuO species on CuZr/SiO2 catalyst is 1.8 times than that of traditional Cu/SiO2 counterpart.Due to the enhanced synergy effect between Cu+and Cuo active sites,a lower activation energy of ester hydrogenation on this ZrO2-doped Cu/SiO2 catalyst is believed to be responsible for the significant improvement. 展开更多
关键词 Copper ZIRCONIA HYDROGENATION ethylene glycol
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SURFACE MODIFICATION OF BLEND FILMS COMPOSED OF SILK FIBROIN AND POLY(ETHYLENE GLYCOL) MACROMER AND THEIR IN VITRO ANTITHROMBOGENICITY 被引量:4
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作者 王松 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第4期399-403,共5页
In order to improve the blood compatibility of silk fibroin (SF), poly(ethylene glycol) macromer (PEGM) in different amounts was added to the SF film to incorporate C=C group into the surface of blend films which were... In order to improve the blood compatibility of silk fibroin (SF), poly(ethylene glycol) macromer (PEGM) in different amounts was added to the SF film to incorporate C=C group into the surface of blend films which were then modified by SO2 gas plasma treatment. ATR-FITR and XPS were used to analyze the chemical change which had occurred on the film's surface. When the content of sulfur on the surface of blend films surpasses 1.59%, the antithrombogenicity of plasma treated films increases remarkably due to surface sulfonation. This result implies that SF with blend of PEGM after SO2 plasma treatment have potential use for making blood-contacting biomaterials. 展开更多
关键词 Silk fibroin Poly(ethylene glycol) macromer PLASMA ANTITHROMBOGENICITY
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An efficient and stable Cu/SiO_2 catalyst for the syntheses of ethylene glycol and methanol via chemoselective hydrogenation of ethylene carbonate 被引量:7
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作者 Jiaju Liu Peng He +3 位作者 Liguo Wang Hui Liu Yan Cao Huiquan Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第8期1283-1293,共11页
The efficient synthesis of methanol and ethylene glycol via the chemoselective hydrogenation of ethylene carbonate(EC) is important for the sustainable utilization of CO_2 to produce commodity chemicals and fuels. I... The efficient synthesis of methanol and ethylene glycol via the chemoselective hydrogenation of ethylene carbonate(EC) is important for the sustainable utilization of CO_2 to produce commodity chemicals and fuels. In this work, a series of β-cyclodextrin-modified Cu/SiO_2 catalysts were prepared by ammonia evaporation method for the selective hydrogenation of EC to co-produce methanol and ethylene glycol. The structure and physicochemical properties of the catalysts were characterized in detail by N_2 physisorption, XRD, N_2O titration, H_2-TPR, TEM, and XPS/XAES. Compared with the unmodified 25 Cu/SiO_2 catalyst, the involvement of β-cyclodextrin in 5β-25 Cu/SiO_2 could remarkably increase the catalytic activity—excellent activity of 1178 mgEC g_(cat)^(–1) h^(–1) with 98.8%ethylene glycol selectivity, and 71.6% methanol selectivity could be achieved at 453 K. The remarkably improved recyclability was primarily attributed to the remaining proportion of Cu~+/(Cu^0+Cu~+). Furthermore, the DFT calculation results demonstrated that metallic Cu^0 dissociated adsorbed H_2, while Cu~+ activated the carbonyl group of EC and stabilized the intermediates. This study is a facile and efficient method to prepare highly dispersed Cu catalysts—this is also an effective and stable heterogeneous catalyst system for the sustainable synthesis of ethylene glycol and methanol via indirect chemical utilization of CO_2. 展开更多
关键词 ethylene carbonate Hydrogenation Β-CYCLODEXTRIN Cu/SiO2 Methanol ethylene glycol
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Catalytic Performance and Texture of TEOS Based Cu/SiO_2 Catalysts for Hydrogenation of Dimethyl Oxalate to Ethylene Glycol 被引量:3
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作者 WANG Shu-rong, YIN Qian-qian and LI Xin-bao State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第1期119-123,共5页
Highly active and selective Cu/SiO2 catalysts for hydrogenation of dimethyl oxalate(DMO) to ethylene glycol(EG) were successfully prepared by means of a convenient one-pot synthetic method with tetraethoxysi lane... Highly active and selective Cu/SiO2 catalysts for hydrogenation of dimethyl oxalate(DMO) to ethylene glycol(EG) were successfully prepared by means of a convenient one-pot synthetic method with tetraethoxysi lane(TEOS) as the source of silica. XRD, H2-TPR, SEM, TEM, XRF and N2 physisorption measurements were performed to characterize the texture and structure of Cu/SiO2 catalysts with different copper loadings. The active components were highly dispersed on SiO2 supports. Furthermore, the coexistence of Cu0 and Cu+ contributed a lot to the excellent performance of Cu-TEOS catalysts. The DMO conversion reached 100% and the EG selectivity reached 95% at 498 K and 2 MPa with a high liquid hourly space velocity over the 27-Cu-TEOS catalyst with an actual cop per loading of 19.0%(mass fraction). 展开更多
关键词 CU/SIO2 TEOS HYDROGENATION Dimethyl oxalate ethylene glycol
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Optimisation of Bio-polyol Production from Cassava Residue Using Ethylene Glycol as the Liquefaction Reagent 被引量:2
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作者 KANG Jiaqing JIN Yanqiao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期945-949,共5页
Cassava residue was liquefied by using ethylene glycol(EG), ethylene carbonate, propylene carbonate and polyethylene glycol(molecular weight: 400 g/mol) as the liquefaction reagent respectively at the temperature of 1... Cassava residue was liquefied by using ethylene glycol(EG), ethylene carbonate, propylene carbonate and polyethylene glycol(molecular weight: 400 g/mol) as the liquefaction reagent respectively at the temperature of 130-170 ℃ with sulfuric acid as the catalyst. The influences of liquefaction parameters, such as the type of liquefaction reagents, mass ratio of EG/cassava residue, liquefaction temperature and time on the properties of the products were discussed. The optimum liquefaction conditions were obtained when the mass ratio of EG/cassava residue was 6:1(w/w), the liquefaction temperature was 150 ℃, the liquefaction time was3 h and the mass fraction of concentrated sulfuric acid/EG was 2.5 wt%. The hydroxyl numbers and residue content of the liquefied products at optimal conditions were 1 137 mgKOH/g and 0.43%, respectively. FT-IR spectrum showed that the liquefaction product of cassava residue was polyether polyol and could be used to prepare polyurethane material or alkyd resins. 展开更多
关键词 CASSAVA residue LIQUEFACTION bio-polyol ethylene glycol
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Synthesis of 2-methylpyrazine from cyclocondensation of ethylene diamine and propylene glycol over promoted copper catalyst 被引量:2
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作者 Fang Li Jing Wei Chu +2 位作者 Yuan Yuan Zhang Ye Qiang Chen Shi Zhong Luo 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第6期752-755,共4页
The 2-methylpyrazine was synthesized by catalytic reaction of ethylene diamine and propylene glycol at 380 ℃. The alumina supported copper catalysts with promoter were prepared by impregnation method, characterized b... The 2-methylpyrazine was synthesized by catalytic reaction of ethylene diamine and propylene glycol at 380 ℃. The alumina supported copper catalysts with promoter were prepared by impregnation method, characterized by ICP-AES, BET and TPR. The results demonstrated that the dehydrogenation was improved by addition of chromium promoter. The selectivity of 2-methylpyrazine reached 84.75%, while the conversions of reactants were also enhanced. 展开更多
关键词 2-METHYLPYRAZINE Copper catalyst DEHYDROGENATION ethylene diamine Propylene glycol PROMOTER
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