Nanoscale
·
2020
·Vol. 12
·期 34
·17812-17820
·
IF 6.895
Longxiang Han,Hengchang Bi,Xiao Xie,Shi Su,Peng Mao,Litao Sun
Materials for emulsion separation with low pressure, high flux and high stability are of great interest in the treatment of oily wastewater. Herein, we report a facile strategy for the fabrication of PDMS and graphene coated melamine sponge (PG-MS), which can efficiently separate oil-in-water emulsions. In PG-MS, melamine sponge (MS) provides a three-dimensional porous structure, graphene constructs hydrophobic microcavities, and PDMS enhances the hydrophobic property of the material, forming a superhydrophobic material. The PG-MS shows high flux (experimentally 10 000 L m−2 h−1, and the effective flux increases with the thickness of the filter layer), high separation efficiency (oil content of the filtered water ∼4.7 mg L−1 can be discharged directly, with oil separation efficiency >99%), low pressure (applied to overcome water's gravity), and high stability (no obvious change in 20 cycles). Our study indicates that PG-MS has a wide range of applications in oil-in-water emulsion separation in industry and environmental sciences.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 46
·26318-26324
·
IF 2.936
Xianbin Huang,Jinsheng Sun,Kaihe Lv,Jingping Liu,Haokun Shen
This study presents an alternative method to enhance the emulsion stability of oil based drilling fluids (OBMs). Modified dimer acid (MDA) was synthesized with a molecular structure having two hydrophilic heads and two hydrophobic tails. Theoretically, the adsorption of MDA on an oil–water interface makes it possible to increase hydrogen bonding between water droplets and form three dimensional networks which benefit emulsion stability. The influence of MDA on the stability of base emulsions was studied by visual observation. Then the stabilization mechanism of MDA was analyzed from the micro and macro points of view by morphology study using a cryo-scanning electron microscope (cryo-SEM) and rheological measurements including viscosity vs. shear rates, zero-shear viscosity (η0), and creep and recovery tests. Experimental results showed that a substantial improvement in emulsion stability was visually observed when the MDA concentration was 2 g L−1. From cryo-SEM observation, a honeycomb structure was observed in the emulsion containing 2 g L−1 MDA, which can provide a physical barrier to restrain the movement of water droplets. In comparison with the rheological behaviors of the emulsion without MDA, a remarkably larger zero-shear viscosity, a solid-like behavior and a greater elasticity were observed when 2 g L−1 MDA was present. Finally, the application in OBMs shows that MDA can largely enhance electrical stability (ES) and reduce the filtration volume. The method proposed in the paper could be used to enhance the stability of w/o emulsions in a variety of fields.
研究领域:
化学工程
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石油工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Hui Liu,Jianying Huang,Zhong Chen,Guoqiang Chen,Ke-Qin Zhang,Salem S. Al-Deyab,Yuekun Lai
In this work, a translucent superhydrophobic coating was fabricated by a simple spray-coating technique using fluorine-free and easily available materials, viz , the hybrids of PDMS and PMMA in THF solution, without any pre-/post-treatment. The combination of the microscale roughness of the sprayed-PMMA, along with the low surface energy PDMS, has contributed to the observed superhydrophobicity. The as-prepared PDMS/PMMA@superhydrophobic surface has displayed a water contact angle of 157.5° and sliding angle of 2.8°. Furthermore, the liquids with various surface tension, ranging from water to various organic liquids, displayed nearly spherical shapes on the superhydrophobic substrate. In addition, this coating has also shown significant stability against sand abrasion and water droplet impact, and was able to maintain its superhydrophobicity after being soaked in strong acid and salkali solutions. Moreover, the superhydrophobic coating was found to be translucent with good visibility of the characters through the coated glass substrate. The transformation from a superhydrophobic state to superhydrophilic state can be realized via a hot-press process, and such a facile technique can be easily applied to potential applications in surface patterning. Additionally, the super-antiwetting surface has been demonstrated for applications in highly efficient oil-water emulsion separation, anti-fouling, and self-cleaning.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
FOOD HYDROCOLLOIDS
·
2023
·
IF 10.7
Jie Zhang,Yunxiao Xie,Cui Liu,Huaqiang Cao,Yan Li,Bin Li,Yangyang Zhang,Shilin Liu
Currently, the cultivation of lactic acid bacteria is mainly carried out by improving the fermentation process and culture conditions, which was difficult to ensure the survival quantity and culture efficiency. The primary purpose of this work was to construct water-in-water (W/W) Pickering emulsion as a microculture for probiotics . The W/W Pickering emulsion consisting of maltodextrin (MD) and hydroxypropylmethylcellulose (HPMC) was constructed by using microcrystal celluloses (MCC) as the Pickering stabilizers. The effects of MCC concentration, NaCl concentration, MRS broth concentration, and pH value on the formation and stability of W/W Pickering emulsion have been investigated. The stability of W/W Pickering emulsions was driven by the electrostatic repulsion provided by the MCC. The stability of the emulsion was reduced by increasing NaCl and MRS broth concentrations, primarily because their charge shielding effect weakened the electrostatic repulsion between the MCC particles. The W/W Pickering emulsion had higher stability in a weakly acidic environment. The results from another trial revealed that Lactobacillus helveticus CICC 22,536 had little influence on the stability of the W/W Pickering emulsion when it was encapsulated in the emulsion. Moreover, Lactobacillus helveticus was able to be cultured in the emulsion, and the numbers of Lactobacillus helveticus after being cultured for 16 h were increased to 1.1 × 10 9 CFU/mL. These findings indicated that the W/W Pickering emulsion provided a new approach and an attractive platform for the cultivation of probiotic bacteria.
研究领域:
微生物学
·
食品科学
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生物工程
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Leqi Cui,Jing Fan,Yifei Sun,Zhenbao Zhu,Jianhua Yi
Salts reduction/substitution have gained a lot interest from food industry since the US Food and Drug Administration (FDA) has issued a draft guidance for salt reduction. However how changes of salts in food formulation could influence lipid oxidation is still not fully understood. Using oil-in-water emulsions stabilized by a natural emulsifier – lecithin at pH 7.0 as a model system, this study evaluated how salts affect the physical parameters of the emulsion, the chelating activity of lecithin and thus the lipid oxidation of these emulsions. Results showed that salts increased the particle size, the negative charge of the oil droplets, and the amount of iron chelated by lecithin. Lipid oxidation lag phases were shortened by addition of salts, by 1 day and 2 days for lipid hydroperoxides and thiobarbituric acid reactive substances measurements respectively. These results provide some new insights on the mechanisms of how salts could affect the lipid oxidation of food emulsions.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Omega
·
2024
·
IF 3.7
Nana Sun,Huina Sun,Jianbo Hu,Shiqi Xu,Lisha Shen,Yuli Ma
In this study, cationic polyacrylamide (CPAM)-coated magnetic nanoparticles (MNPs) Fe3O4@CPAM were synthesized for treating heavy O/W emulsions. This Fe3O4@CPAM was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and vibrating sample magnetometry (VSM) techniques, and its synergistic performances with microwaves were evaluated in detail with respect to the microwave radiation power, radiation time, and magnetic nanoparticle concentration. On this basis, the distribution of oil droplets and the wettability and chargeability of magnetic nanoparticles were measured without or with microwave radiation using biomicroscopy, contact angle measurement instrument, and a ζ-potential analyzer, thus revealing the synergistic demulsification mechanism between microwave and magnetic nanoparticles. The results showed that excessively high or low microwave radiation parameters had an inhibitory effect on the magnetic nanoparticle demulsification, and microwave promoted the magnetic nanoparticle demulsification only when the radiation parameters were in the optimal range. In addition, the water separation rate showed an increasing and then decreasing trend with the increase of magnetic nanoparticles concentration, with or without microwave action. As an example, the water separation rate of the emulsion for 1 h was 21.34% when the Fe3O4 concentration was 175 mg/L without microwave action, while it increased to 55.56% with microwave action. In contrast, when the concentration of Fe3O4@CPAM was 175 mg/L, the water separation rate was 42.86% without microwave radiation, while it was further increased to 77.38% under microwave radiation. These results indicate that magnetic nanoparticles and their complexes significantly affect the water separation process under different conditions. There is a more obvious coupling synergistic effect between Fe3O4@CPAM and microwave. This was due to the lower absolute potential of Fe3O4@CPAM and its higher hydrophobicity.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Wenbo Jiang,Yiwen Wei,Shilong Li,Chenye Dai,Can Yuan,Jian Lu,Dong Zou,Tianxiang Yu,Yuqing Sun,Wenheng Jing
Bio-heavy oil with high oxygen content and combustion calorific value has attracted lots of attention as a green and sustainable fuel to cope with the increasingly severe energy shortages. However, the high salt content limits its combustion utilization due to potential risks such as equipment corrosion and wear blockage. The traditional desalination method using sulfuric acid causes a large amount of wastewater, Herein, we propose an assisted metal-ion interphase mass transfer desalination strategy by preparing carbonated water-in-bio-heavy oil (CW/O) emulsions with continuous membrane emulsification. α-Al 2 O 3 membrane with an average pore size of 600 nm was selected as the emulsification medium. Saturated carbonic acid solutions as a dispersed phase were pressed through the membrane pores into bio-heavy oil to form uniform micron-sized CW/O emulsions. The prepared CW/O droplets provide a large interphase mass transfer interface which assists the hydrolysis of fatty acid salts of bio-heavy oil in the acidic environment and yields an efficient transfer of metal ions. As a result, the CW/O emulsion with an average droplet size (D 3,2 ) of 4.29 μm and a specific surface area of 139.63 m 2 /m 3 was prepared at a pressure of 0.5 MPa, achieving a salt removal efficiency of up to 85.62 %. This study provides a novel chemical-free and effective strategy for efficient oil product refining while utilizing CO 2 through the continuous preparation of micron-sized CW/O droplets with sufficient interphase mass transfer area.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Juan Zhai,Zihan Li,Hengyang Mao,Xiuyang Zou,Shouyong Zhou,Meisheng Li,Minghui Qiu,Yan Zhang,Shanshan Xia,Yijiang Zhao
The surge in oil-in-water (O/W) emulsions poses a threat to the ecological environment. Membrane separation technology can achieve complete O/W emulsion separation through size sieving; however, its efficiency is limited by membrane fouling. In this study, an efficient O/W separation membrane with passive and positive anti-fouling properties was fabricated using Fe 3 O 4 functionalized attapulgite (ATP) nanofibers. The anti-fouling mechanism of the multifunctional membranes for the separation of various O/W emulsions was studied. During separation process, a hydration layer, which mitigates oil adhesion with binding energy as low as −169 kcal·mol −1 , forms on the interface of Fe 3 O 4 -ATP. When a cationic surfactant is present, positively charged oil droplets are attracted to the membrane surface, where they compress against each other, leading to demulsification and escape. Synergistic effects including electrostatic shielding, interaction energy, and steric hindrance were demonstrated through characterization and simulation. Our findings showed that the membrane exhibited a high filtration efficiency with an oil rejection of over 99 % and a steady flux of over 73 % of its initial value. After filtration, oil fouling degraded into smaller sizes and escaped from the membrane structure through the Fenton-like catalytic function of Fe 3 O 4 , resulting in a flux recovery ratio of up to 90 %. This study provides a reference for the construction of multifunctional membranes for efficient separation processes and advancing anti-fouling research on membrane interfaces.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Han Jia,Jiajun Dai,Pan Huang,Yugui Han,Qiuxia Wang,Juan He,Jinyong Song,Xin Wei,Hui Yan,Dexin Liu
It is greatly desired to develop a high-efficiency demulsifier for the treatment of O/W emulsions in the production fluids of the petroleum industry. In this study, the amphiphilic Janus-SiO2 nanoparticles (Janus-C18) was synthesized and used as a demulsifier for surfactant-stabilized O/W emulsions. The successful preparation of Janus-C18 was verified by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and contact angle measurements. Then, Janus-C18’s demulsification efficiency was systematically evaluated by the bottle test. Various silica nanoparticles and emulsifier were employed in the control experiments. Based on the Janus-C18’s demulsification performance in different conditions and the ζ-potential measurement, the possible demulsification mechanism of Janus-C18 was proposed. Furthermore, Janus-C18 exhibited excellent performance in separating oil from crude oil/water emulsions at a relatively low concentration (150 mg/L), with the oil removal rate exceeding 99%.
研究领域:
化学工程
·
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2023
·
IF 2.2
Yu Zhang,Jiazhe Kuang,Bin Li,Yuanzhu Mi,Ying Yang,Xuening Feng
In this work, a PAMAM@SiO2 demulsifier was synthesized by the reaction of a hyperbranched poly (amido amine) (PAMAM) and KH570 modified SiO2. The structure, morphology and composition of PAMAM@SiO2 were characterized by FT-IR, SEM and EDS. The effect of the concentration of PAMAM@SiO2, salinity and temperature on the demulsification performance was systematically studied. The results showed that the transmittance of aqueous phase after demulsification could reach as high as 92.1% at optimal conditions, and corresponding oil removal rate was 99.53%. Interfacial activity, three-phase contact angle, self-assembly of interfacial film and dynamic interfacial tension were investigated to explore the demulsification mechanism. Also, the aggregation process of oil droplets in emulsion was observed with a microscope. It indicates that the PAMAM@SiO2 demulsifier has a potential application in the treatment process of oily wastewater.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2023
·
IF 6
Yuqi Tang,Mingzhao Zhu,Junhong Chen,Xuebiao Sun,Huan Li,Zhijie Hu,Suman Li,Qian Qu,Zejun Zhang,Yuanzhu Mi
The petroleum industry produces a large volume of water-in-oil (W/O) emulsion annually, which has detrimental consequences for both the industry and the environment. Therefore, effective demulsification of these emulsions is crucial. In current work, a low-temperature demulsifier (EBTA) for W/O emulsions was synthesized using PET waste plastic as starting materials through a simple method. Chemical structure of EBTA was characterized by FT-IR and 1 H NMR. The demulsification performance was assessed using bottle-test method, and a comprehensive examination was conducted on the influence of EBTA concentration, settling time, temperature, pH value, and salinity on the demulsifying efficiency (DE). At a low temperature of 40 ℃ and a concentration of 250 mg/L, EBTA achieved a DE of 95.36% in an Emul30 emulsion, while a DE of 100% could be obtained in an Emul70 emulsion. Furthermore, EBTA demonstrated excellent tolerance for salts, acids and alkalis. In addition, the demulsification mechanism of EBTA was investigated using various techniques, such as interfacial tension (IFT), zeta potential, three-phase contact angle and coalescence time of droplets. The results revealed that EBTA had a lower IFT and was easily adsorbed on the oil–water interface. This led to the damage of the interface film and facilitated the oil–water separation. Due to the simple and safe synthesis process and remarkable demulsification performance, EBTA is a promising demulsifier for separating W/O emulsions.
研究领域:
環境科學
·
石油化工
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2018
·
IF 3.789
Alessio Caciagli,Mykolas Zupkauskas,Aviad Levin,Tuomas P. J. Knowles,Clément Mugemana,Nico Bruns,Thomas O’Neill,William J. Frith,Erika Eiser
Many industrial soft materials include oil-in-water (O/W) emulsions at the core of their formulations. By using tuneable interface stabilizing agents, such emulsions can self-assemble into complex structures. DNA has been used for decades as a thermoresponsive, highly specific binding agent between hard and, recently, soft colloids. Up until now, emulsion droplets functionalized with DNA had relatively low coating densities and were expensive to scale up. Here, a general O/W DNA-coating method using functional nonionic amphiphilic block copolymers, both diblock and triblock, is presented. The hydrophilic poly(ethylene glycol) ends of the surfactants are functionalized with azides, allowing for efficient, dense, and controlled coupling of dibenzocyclooctane-functionalized DNA to the polymers through a strain-promoted alkyne–azide click reaction. The protocol is readily scalable due to the triblock’s commercial availability. Different production methods (ultrasonication, microfluidics, and membrane emulsification) are used with different oils (hexadecane and silicone oil) to produce functional droplets in various size ranges (submicron, ∼20 and >50 μm), showcasing the generality of the protocol. Thermoreversible submicron emulsion gels, hierarchical “raspberry” droplets, and controlled droplet release from a flat DNA-coated surface are demonstrated. The emulsion stability and polydispersity is evaluated using dynamic light scattering and optical microscopy. The generality and simplicity of the method opens up new applications in soft matter, biotechnological research, and industrial advances.
研究领域:
软物质科学
·
材料科学
·
生物技术
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）