ENERGY & FUELS
·
2025
·
IF 5.3
Kaixin Jin,Xiao Lu,Zhouwen Li,Guangmai Zhao,Wanpeng Li,Xuewei Zhang,Haiyong Wang,Junzhang Wu,Xiaobin Xie,Li Zhao,Tianhan Zhu,Yuhe Liao,Chenguang Wang,Dalei Zhang
Cellulosic ethanol is a pivotal biofuel, and its chemocatalytic production from lignocellulosic biomass is crucial for addressing global energy challenges. In this study, a series of Pt-loaded catalysts were developed by sequentially loading varying weight percentages (wt %) of Pt and W onto SiO2 carriers using the impregnation method. The catalysts were comprehensively characterized through X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy to analyze the metal dispersion and active oxidation states on the SiO2 support. Under hydrothermal conditions (240 °C and 4 MPa H2), cellulose was directly converted to ethanol in the aqueous phase, achieving an ethanol yield of 37.5 C%. The catalysts demonstrated excellent stability, maintaining high activity over at least five consecutive reaction cycles. Notably, the WO3 component played a key role in facilitating C–C bond cleavage and hydrolyzing cellulose into glucose and ethanal intermediates. These intermediates were swiftly transferred to the Pt active sites, further promoting the formation of ethylene glycol. Among the catalysts, 3%Pt-15%WO3/SiO2 exhibited optimal performance due to its well-balanced ratios of Pt0 and Pt2+, which enabled selective C–O bond activation and significantly enhanced ethanol production.
研究领域:
生物化学
·
催化化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2021
·Vol. 11
·期 11
·1383
·
IF 2.589
Panpan Zhang,Lize Zhang,Ke Zhang,Jiupeng Zhao,Yao Li
Due to the high value of its dielectric constant, polyimide does not meet the requirements of the development of integrated circuits and high-frequency printed circuits. The development of novel low dielectric constant polyimide materials for the preparation of flexible copper clad laminates is of theoretical and practical significance in the application of polyimide for 5G communications. In this work, different fluorinated graphene/polyamic acids (FG/PAA) were used as the precursor, and the porous polyimide film was successfully prepared by phase inversion. The dielectric constant of the porous polyimide film is relatively low, being less than 1.7. When the content of fluorinated graphene is 0.5 wt%, the overall dielectric performance of the porous film is the best, with a dielectric constant of 1.56 (10 kHz) and a characteristic breakdown field strength of 56.39 kV/mm. In addition, the mechanical properties of the film are relatively poor, with tensile strengths of 13.87 MPa (0.2 wt%), 13.61 MPa (0.5 wt%), and 6.25 MPa (1.0 wt%), respectively. Therefore, further improving the breakdown resistance and mechanical properties of the porous film is essential for the application of porous ultra-low dielectric polyimide materials.Keywords:polyimide;phase inversion;dielectric constant;porous films
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2011
·
IF 2.775
Xiao-Lin Li,Li-Ping Zhu,Bao-Ku Zhu,You-Yi Xu
It is well-known that cellulose is difficult to dissolve in common organic solvent and be directly processed into porous membrane. In this work, using ionic liquid, 1-allyl-3-methylimidazolium chloride (AMIMCl) as solvent, high flux and anti-fouling cellulose nanofiltration (NF) membranes were fabricated by phase inversion method from 8.0 wt.% of cellulose/AMIMCl solutions. Pure water was employed as the non-solvent in phase inversion process. From the result of polarized light microscopy, we found that cellulose was completely dissolved in the AMIMCl at 90 °C. The characterizations of Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectroscopies showed that no obvious changes occurred in the chemical structure of cellulose after membrane formation, but the crystallinity had a remarkable decreased. Membrane morphologies of the fabricated cellulose membranes including the cross-section and the surface were analyzed by scanning electron microscopy (SEM). It was found that the AMIMCl had a distinctive effect on phase inversion process and the cellulose selective layer displayed a macrovoid-free and relatively dense layered structure. Based on the filtration experimental results, the pure water permeation flux of the membranes reached 128.5 L/m 2 h under 0.4 MPa, and the molecular weight cut-off was less than 700 Da. The membranes exhibited a good stability and anti-fouling ability in water-phase separation process, and were suitable as NF membranes to separate the organic compounds with a medium molecular weight.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2024
·
IF 4.1
WenKai Cao,BinXiao Wei,YinChuan Pu,LiPeng Wang,SiQi Su,YongPing Bai
This article aims to propose a low-energy method for micron dispersion of entangled polymers. We chose Ethylene-Propylene-Diene Monomer (EPDM) as the entangled polymer and acrylic esters as the dispersants to prepare the organic dispersion of the entangled polymer based on the theory that in-situ polymerization of acrylic esters had the higher solubility parameter than the original monomer. The dispersion process of entangled polymer was similar to the phase inversion of emulsion due to the maximum viscosity and minimum interfacial tension at the point of dispersion. Specifically, the average diameter of the dispersed entangled polymer was 5–6 μm. The system could still maintain excellent dispersion stability without additional dispersants. Rheology characterized that the introduction of aliphatic isocyanate derivatives reacting with hydroxyl groups in the polyacrylate to form the cross-linked skeleton could enhance the stability of the system. Excitingly, this organic dispersion allowed flexible printed circuit to fold at any angle and direction when used as the coating, and the coating still maintained excellent dispersibility, flexibility, insulation, and adhesion after aging tests. This low-energy method for micron dispersion of entangled polymers could expand their applications in coatings and other fields while maintaining their own characteristics.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2021
·
IF 6.953
Binqing Zhao,Qi Zhou,Chenxi Lou,Xinpeng Jin,Wei Li
Carbon dioxide (CO 2 ) assisted synthesis of water-soluble silver nanoparticle with a narrow particle size distribution is reported here based on the phase-inversion procedure. Bio-derived chitosan (CS) is used to stabilize the metal nanoparticles according to its abundant functional groups. Formic acid is employed as both a solvent (for the polymer) and a reductant for in-situ reducing the silver precursor along with the solvent evaporation. CO 2 is utilized to combine with the amino groups of CS, reducing the viscosity of chitosan/formic acid solution and limiting the formation of hydrogen bonds . This promotes the stabilization and reduction efficiency of silver nanoparticles. In particular, 100% of Ag metal nanoparticles with the size of 7.5 ± 2.3 nm is successfully synthesized with the assistance of CO 2 . Interestingly, the synthesized CS/Ag nanocomposites are water-soluble owing to the formation of carbamate groups. This water-soluble silver nanoparticle presents an exceptional performance in the selective reduction of 4-nitrophenol, where the turnover frequency (TOF = 599 h −1 ) is even double with respect to the CO 2 free system.
研究领域:
材料科学
·
生物化学
✓ 已验证
DOI
高影响因子
Crystals
·
2020
·Vol. 10
·期 1
·39
·
IF 2.404
Xiaomin Guo,Bin Zheng,Jinlei Wang
Composite materials that contain metal-organic frameworks (MOFs) as a filler and a polymer matrix have attracted attention because they present a combination of high porosity and structural integrity. Phase compatibilities of the MOF and polymer play a vital role in the formation of the composites. In particular, the stiff polymer cannot easily adapt to penetrate into the surface pore of MOF and mainly depends on chemical attractions to form the MOF/polymer composites. We report the synthesis of MOF/polyethersulfone (Young’s modulus = ~2.6 GPa) via different fabrication methods, different MOF types and particle sizes, and different solvents. The formed network structures are robust, monolithic composites with 60% MOF loadings; also, the MOF surface area and porosity were fully preserved. The study explored the formation of the composite between MOF and a stiff polymer and encourages the design of more MOF/polymer composite materials across a wide range of applications.Keywords:metal-organic framework;composite materials;interface compatibility;phase inversion
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Lu Liu,Xiaolin Pu,Yan Zhou,Xiaodong Wu,Dan Luo,Zhifeng Ren
Pickering emulsions show great potential for the petroleum industry, especially those that can realize emulsion inversion in basic conditions. Developing a simple and green approach to control emulsion inversion in basic conditions is highly desirable for harsh conditions and complicated operations. Here we report novel phase inversion of a Pickering emulsion through the controlled wettability of silica nanoparticles (NPs) by N-(2-((2-aminoethyl)amino)ethyl)octadecenamide (C18PDA) with Na2CO3 salt addition. A transitional phase inversion from an oil-in-water (O/W) emulsion to a water-in-oil (W/O) emulsion occurs with increasing C18PDA surfactant concentration for a given amount of Na2CO3 salt. A subsequent phase inversion from a W/O emulsion to an O/W emulsion then occurs with increasing Na2CO3 salt concentration at a low amount of C18PDA surfactant, and demulsification occurs when the Na2CO3 salt concentration is above 94 mM. The stable W/O Pickering emulsions are formed by virtue of adsorption of the C18PDA surfactant onto the silica surfaces, which imparts hydrophobicity to the inherently hydrophilic silica NPs and facilitates strong flocculation of the silica particles in the polar solution. However, the hydrophobicity of the silica NPs is reduced by salinity and is suitable for creating O/W emulsions due to the reduced interactions between the NPs and the C18PDA surfactant. The possible mechanism for emulsion inversion was investigated by characterizing turbidity, surface tension, contact angle, Fourier transform infrared spectroscopy with thermogravimetric analysis, zeta potentials, etc. The rheological properties of the reversible Pickering emulsion show that there is a smooth transition at the transitional inversion point, which differs from conventional surfactant-stabilized emulsions, in which the viscosity decreases to the minimum at the transitional inversion point. The emulsion phase inversion was also found to be conducive to improving the efficiency of filter-cakes cleanup. We anticipate this smart system to be easily operated and environmentally friendly, making it potentially applicable to real oil fields.
研究领域:
石油工程
·
材料科学
·
界面化学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 27
·10410-10423
·
IF 0
Yang Yang,Lei Miao,Jiwen Hu,Guojun Liu,Yuanyuan Tu,Shudong Lin,Feng Liu,Fei Li,Yan Wu,Ganwei Zhang,Hailiang Zou
An amphiphilic binary graft copolymer polysulfone-graft-[poly(methyl methacrylate)-random-poly(acrylic acid)], PSf-g-(PMMA-r-PAA), was synthesized via a combination of atom transfer radical polymerization (ATRP) and click chemistry. This copolymer and polysulfone (PSf) were used to prepare porous membranes through the phase inversion method, which involved dissolving the polymers in a common solvent N-methyl pyrrolidone (NMP), casting the solution onto a glass plate to obtain a film, and subsequently immersing this film into a coagulant (a mixture of dimethylformamide and water at a given pH). The surfaces of the membrane and its pore walls were covered by the copolymer, and these surfaces were enriched with PAA domains due to the immiscibility of PAA and PSf and the miscibility of PMMA and PSf. More specifically, while the hydrophobic PMMA component served as an anchor to fix the graft copolymer onto the PSf bulk substrate, the hydrophilic PAA component assembled and became exposed at the surfaces of the membrane and the pore walls. Factors influencing this surface AA concentration or carboxyl group content (CGC) enrichment and the surface and pore morphologies of the membranes include the ratio between the amount of the copolymer and PSf in the mixture, the solvent quality of the coagulant for PSf, and the temperature as well as the pH of the coagulant. These factors have been systematically adjusted to optimize the hydrophilization of the PSf membrane and the resultant membranes have been characterized by water contact angle (WCA) measurements, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). Optimization of the phase inversion process yielded membranes with nearly complete surface coverage by PAA, even when the graft copolymer represented only 8 wt% of the membrane's composition. The hydrophilized membranes exhibited increased water flux and even pH-responsive water flow without adversely affecting their mechanical properties. In addition, these hydrophilic membranes exhibited long-term stability. Therefore, this novel binary amphiphilic graft copolymer-based approach for membrane modification may be of commercial value.
研究领域:
材料科学
·
化学工程
·
膜技术
✓ 已验证
DOI
DESALINATION
·
2010
·
IF 2.034
Zhenghua Zhang,Quanfu An,Yanli Ji,Jinwen Qian,Congjie Gao
The zero shear viscosity of two kinds of polysulfone (PSF) casting solutions and the morphology and permeability of their membranes prepared via the phase-inversion process were investigated. The zero shear viscosities, dominated by changing the concentration of PSF and the molecular weight of poly(vinyl pyrrolidone) (PVP) additive for the PSF/N, N-Dimethylacetamide (DMAC) binary system and PSF/DMAC/PVP ternary system respectively, were measured by a falling sphere viscometer . The cloud point of solutions was investigated in the cloud point experiment, and the phase-inversion process was monitored by the light transmittance apparatus. The surface and cross-section morphology of the corresponding membranes were characterized by SEM, and the water flux of the membranes was performed in the permeation experiment. Increasing the viscosity of the casting solution leads to the less porous surface and thick-skinned top-layer of the membrane. These experimental results are attributed to the mutable thermodynamic property of the system and the poor diffusion between components during the phase-inversion process, and finally results in the low water flux of PSF membranes. It suggests that the zero shear viscosity of the casting solution is one of the most important parameters for the morphology and permeability of membranes prepared via the phase-inversion process with the same coagulation bath .
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Micromachines
·
2020
·Vol. 11
·期 7
·681
·
IF 2.524
Shanguo Zhang,Guiling Li,Jia Man,Song Zhang,Jianyong Li,Jianfeng Li,Donghai Li
Three-dimensional (3D) bioprinting is a novel technology utilizing biocompatible materials, cells, drugs, etc. as basic microcomponents to form 3D artificial structures and is believed as a promising method for regenerative medicine. Droplet-based bioprinting can precisely generate microspheres and manipulate them into organized structures with high fidelity. Biocompatible hydrogels are usually used as bioinks in 3D bioprinting, however, the viscosity of the bioink could be increased due to the additives such as cells, drugs, nutrient factors and other functional polymers in some particular applications, making it difficult to form monodispersed microspheres from high-viscosity bioink at the orifice of the nozzle. In this work, we reported a novel microfluidic-based printing nozzle to prepare monodispersed microspheres from high-viscosity bioink using the phase-inversion method. Different flowing conditions can be achieved by changing the flow rates of the fluids to form monodispersed solid and hollow microspheres using the same nozzle. The diameter of the microspheres can be tuned by changing the flow rate ratio and the size distribution of the microspheres is narrow. The prepared calcium alginate microspheres could also act as micro-carriers in drug delivery.Keywords:droplet-based bioprinting;microfluidic system;phase-inversion method;microcomponent
研究领域:
生物医学工程
·
再生医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Sustainable Metallurgy
·
2021
·Vol. 7
·期 4
·1643-1653
·
IF 2.347
Li Yun,Chang Cong,Jie Yafei,Jin Wei,Chen Yongming,Wan Xingbang,Tang Chaobo,Yang Shenghai
A promising copper–cobalt slag cleaning technique has been proposed, involving employing gypsum wastes as a sulfurizing agent to sulfurize copper, cobalt, and iron and enrich a condensed matte from copper–cobalt slag. This work thermodynamically investigated the phase conversion mechanism in the Cu 2 O–CoO–Fe 3 O 4 –FeO–CaSO 4 –C system, at the same time, calculated the equilibrium of the “matte–slag–gas.” The results show that CaSO 4 can be selectively reduced to CaS without self-decomposition to CaO and SO 2 . Cu 2 O and CoO lost in slag can be sulfurized by CaS to Cu 2 S and CoS. Fe x O y tended to stay in oxides. Whereas, in the “matte–slag–gas” equilibrium system, a matte containing Cu 2 S, CoS, FeS, Fe, Co, and Cu was obtained. In addition, industrial copper flash smelting slag was used to conduct beach-scale experiments to validate the thermodynamic modeling results and detect the copper and cobalt recovery efficiency. The experimental results reveal that more than 92% copper and 94% cobalt were recovered in matte. The sulfur and calcium in gypsum waste transferred to matte and cleaned slag, respectively. Thus, the values in the slag and gypsum wastes can be recycled simultaneously. Graphical Abstract
研究领域:
冶金工程
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2021
·
IF 8.742
Yaoyao Zhu,Yeqiang Lu,Yuxin Shi,Xueting Zhao,Congjie Gao,Lixin Xue
Super-wetting membranes have recently attracted widespread attention for their promising application in oil/water separation. Generally, the preparation procedures of the super-wetting membranes are quite arduous, and it remains challenging to design a reasonable fabrication method. In this work, we present a facile method to prepare polyvinylidene fluoride (PVDF) based super-wetting membranes from direct immobilization of nanoparticles by in-situ polymerization and ionic cross-linking during phase inversion. The as-prepared membranes exhibited excellent amphiphilic properties, and had switchable wettability between super-oleophobic underwater and super-hydrophobic under oil. The modified PVDF membranes with such switchable wettability had high separating performance towards both surfactant-stabilized water-in-oil and oil-in-water emulsions under gravity and exhibited good durability and recyclability. This research not only provides a simple preparation method of amphiphilic super-wetting membranes, but also the unique performance of the membrane in water treatment.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）