JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
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2017
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IF 1.591
Shuang Zhang,Ting Lü,Dongming Qi,Hongting Zhao
Chitosan (CS)-based flocculants, denoted as CS-g-PAM and CS-g-PDBC, were successfully prepared via graft copolymerization of CS with acrylamide (AM) or dimethyl acryloyloxyethyl benzyl ammonium chloride (DBC). The grafting was confirmed by Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS). The flocculation performance of CS-g-PAM and CS-g-PDBC, as well as flocculants such as cationic polyacrylamide (CPAM), polyaluminum chloride (PAC), and CS, was evaluated and compared for treating emulsified oil wastewater. It was found that CS-g-PDBC exhibited excellent flocculation performance under both acidic and neutral conditions, while CS showed better flocculation ability under alkaline condition. The flocculation mechanism of CS and CS-g-PDBC was investigated via zeta potential measurements. Results showed that different flocculation mechanisms were involved at various pH levels. As regarding CS, the flocculation mechanism is mainly charge neutralization, patching, and sweep floc under acidic, neutral, and alkaline conditions, respectively, while for CS-g-PDBC, patching was the dominant mechanism under both acidic and neutral conditions.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Hailin Yu,Huili Zhang,Chunlong Sun,Wen Yuan,Hongliang Li,Wei Jiang,Long Dong,Yingjun Wang,Hongsheng Liu
The complexity of oily sewage from oilfields has risen with the advancement of polymer flooding technology, thereby increasing the treatment challenge. In this study, a composite coagulant, PVPAM-PPFS, was proposed, inspired by octopus tentacles, with PVP as the backbone. FTIR , 1 H NMR and Rg radius of gyration were used to characterize the functional groups and conformation of PVPAM-PPFS in aqueous environments. The composite coagulant exhibits facile dispersion in water. Upon hydrolysis of PVPAM-PPFS, numerous molecular chains resembling octopus tentacles are formed and confirmed through Atomic Force Microscopy (AFM). When applied to oily sewage in oilfields, PVPAM-PPFS demonstrates enhanced interaction with emulsified oil layers, capturing colloidal particles in water and thereby facilitating efficient separation of oil, water, and flocs. Lastly, the mechanism of PVPAM-PPFS was analyzed through a combination of coagulation experiments and detection of floc morphology. PVPAM-PPFS will better interact with colloidal particles in water through increased charge neutralization, bridging adsorption, and sweeping capabilities. Significantly, an enhanced crude oil recovery rate is observed from the recovered oil droplets following the disruption of the emulsion layer.
研究领域:
环境科学
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化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2019
·Vol. 55
·期 11
·4578-4591
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IF 3.442
Diao Shuai,Liu Huie,Chen Shuang,Xu Wenlong,Yu Anran
Graphene aerogels with different pore sizes, volumes and degrees of reduction were prepared through Pickering emulsion method. The controllable preparation of aerogels was achieved. The graphene aerogels prepared were characterized by FTIR and XPS. The adsorption capacity of pure oil by graphene aerogel was investigated. The graphene aerogels can adsorb pure oil quickly and hardly adsorb water. Linear relation exists between saturated adsorption capacities of graphene aerogels on oil and the densities of the oil adsorbed. The volume of the adsorbed organics on unit mass of the aerogel is 186.46 cm 3 g −1 . The occupancy rate in the aerogel pores is 73.71%. The factors affecting its adsorption rate on emulsified oil were investigated. The adsorption curves of graphene aerogels on emulsified oil conform to the pseudo-second-order kinetic model. The larger the inner diameter of the pore size in the graphene aerogels and the larger the outer surface area, the faster the adsorption rate of the emulsified oil would be. The adsorption rate of the rough internal with higher hydrophobicity decreases slightly, but as the degree of reduction increases, the hydrophobicity gradually increases and the adsorption rate increases gradually, so there should exist an optimum hydrophobicity value of aerogels for the adsorption of emulsified oil in water.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
Journal of Cleaner Production
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2023
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IF 11.1
Bokun Chen,Caichun Zheng,Jicheng Bi,Xuan Qu,Rong Zhang,Xinbo Liu,Yanqi Yang
Coal pyrolysis wastewater pretreatment suffers from equipment fouling and inferior mass transfer efficiency brought by low emulsified oil removal efficiency. This paper comprehensively analyzed the properties of emulsified oil and found this inadequacies attribute to its high stability and penetrability derived from high ζ potential of −33.1 mV and tiny average particle size of 114.7 nm in initial condition. H 3 O + adjustment is developed to compress diffusion layer thickness and facilitate natural coalescence of emulsified oil droplets . Results of H 2 SO 4 acidification present the peaks of average particle size sustainably stabilized between 782.9 and 1009.0 nm and emulsified oil was mostly coagulated and subsequently settled/floated without further treatment. CO 2 was selected as a suitable donor of H 3 O + to improve application potential, and flocculants was coupled with pressurized dissolved CO 2 to intensify emulsified oil removal whose optimal efficiency achieved 93.82 wt% by changing flocculant types and operation conditions. Response surface analysis results introduced emulsified oil removal efficiency reached 95.17 wt% at PAC concentration of 1065 mg/L, CPAM concentration of 20 mg/L and operating pressure of 0.67 MPag. For renovation projects with limitations, the optimal emulsified oil removal efficiency achieved 94.33 wt% at PAC concentration of 1032 mg/L, CPAM concentration of 21 mg/L and operating pressure of 0.60 MPag. Process simulation of sour gas and ammonia stripper signified that CO 2 addition has little effect on current industrial process. By comparison, the proposed approach performs high efficiency, low impact to wastewater, strong feasibility, and great prospect in pretreatment.
研究领域:
环境工程
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Jiangya Ma,Wei Xia,Rui Zhang,Lei Ding,Yanli Kong,Huiwen Zhang,Kun Fu
In this work, modified chitosan flocculants (MCS) was synthesized by using chitosan (CS), acrylamide, cationic monomers and hydrophobic monomers via low-pressure UV-initiated copolymerization. The flocculation performance of MCS was evaluated in emulsified oily wastewater treatment. The effect of cationic and hydrophobic structure on oil removal was studied, and the interactions between these functional groups and the components in oil were also analyzed. Results suggested that MCS flocculants exhibited excellent oil removal efficiency in a wide pH range (2.0‒10). The flocculation efficiency of 91 % was achieved at the dosages of 0.6 mL/L (6 mg/L). During pH of 2.0-10, the optimal cationic and hydrophobic monomer was DMC and VT, respectively. Silane groups were favorable for oil removal than the other hydrophobic structures. The cationic groups expanded the optimal pH range of MCS in flocculation, whereas hydrophobic groups considerably reduced the dosage of MCS. The experimental results showed that alkane, cyclic aromatic hydrocarbon compounds in oil can be easily removed by using MC4, whereas cycloalkanes compounds was effectively removed by MC6 and MC7 because of preferable demulsification capacity, and the hydrophobic interaction, interfacial adsorption and electrostatic attraction played the dominant in flocculation. Thus, the synthesized MCS is favorable for emulsified oily wastewater treatment.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2021
·
IF 10.588
Jiangya Ma,Xue Fu,Wei Xia,Rui Zhang,Kun Fu,Genyu Wu,Bangtao Jia,Sha Li,Jincheng Li
In this work, a novel recyclable covalently bonded magnetic flocculant (FS-MC) was successfully prepared by combining chitosan-based modified polymers (MCS) with Fe 3 O 4 @SiO 2 through a silane coupling agent. The covalent bond Fe–O–Si–O–C and the core–shell structure of FS-MC were confirmed through several characterization methods. The emulsified oily wastewater flocculation performance and mechanism by using FS-MC were evaluated and studied. Results showed that 94.47%, 93.95%, and 92.98% of emulsified oil could be removed by using FS-MC1, FS-MC2 and FS-MC3 at dosages of 2.0, 2.5, and 2.0 mg/L, respectively. Furthermore, FS-MC exhibited an excellent behavior on the removal of organic compounds with molecular weight > 10 kDa, including long chain alkanes, cycloalkanes , and aromatic hydrocarbon compounds. In addition, triple-phase separation of oil, water and flocculants was achieved by using magnetic FS-MC. Due to the introduction of cationic and hydrophobic groups in FS-MC, charge neutralization, compression double electric-layer action, hydrophobic interaction, interfacial adsorption bridging and sweep-flocculation synergistically contributed and enhanced the removal of emulsified oil. Recycling experiments also showed that no obvious decrease of oil removal rate was observed by using magnetic FS-MC flocculants in five cycles.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Yantao Song,Meng Yan,Zixuan Xu,Benqiao He,Biao Wu,Jianxin Li,Zhenyu Cui
In this study, the 3-Aminopropyltriethoxysilane (APTES) was first grafted onto TiO 2 nanoparticles (APTES-TiO 2 nanoparticles), which were then introduced the membrane surface by reacting with anhydride on the membrane surface and Schiff base reaction with the PEI-TA. There are two types of hollow fiber hybrid membranes with varying nanoparticle distributions were constructed. The influence of hybrid mode on the ability of anti-oil fouling was researched. The results indicated that the PVDF@TiO 2 hybrid membrane has a flux recovery rate of 96.68 % and a total flux decline rate of 15.52 %, indicating a good anti-emulsified oil fouling performance. By characterizing the anti-oil droplets adhesion, water-binding capacity, surface charge of membrane and concentrate system coacervate size, the coalescence ability of the hybrid membrane to the oil droplets and the spreading behavior of oil droplets on the surface were uncovered. Ultimately, the anti-fouling mechanism “hydration layer &rigid layer obstruction-electrostatic coalescence” was proposed, which can reasonably explain the weakness of the interplay between the membrane surface and oil droplets, thus slowing down the attaching and spreading of emulsified oil droplets. This study laid the foundation for developing hybrid membranes with high resistance to emulsified oil fouling ability. The proposed anti-fouling mechanism can provide new ideas for the efficient purification of oily wastewater.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2019
·
IF 3.074
Ting Lü,Chenglin Luo,Dongming Qi,Dong Zhang,Hongting Zhao
A series of chitosan-based flocculants have been successfully synthesized by grafting poly(acrylamide) (PAM) or poly(dimethyl acryloyloxyethyl benzyl ammonium chloride) (PDBC) onto chitosan (CS) molecular chain and then characterized by using multiple techniques. The synthesized CS-based flocculants were subsequently used to flocculate the emulsified oil droplets in simulated oily wastewater under various conditions. It was found that the PDBC-grafted CS (CS-g-PDBC) showed better flocculation performance than those of CS and two other commonly used flocculants, i.e. cationic PAM (CPAM) and polyaluminum chloride (PAC). Moreover, the flocculation efficiency of CS-g-PDBC was gradually enhanced with increasing grafting ratio of PDBC, while declined after the introduction of grafted PAM chains. The cationic and hydrophobic groups of PDBC could significantly promote the adsorption of flocculant molecular chains on the negatively charged oil droplets via electrostatic attraction and hydrophobic interaction, thereby facilitating subsequent flocculation process. In addition to the adsorption bridging mechanism, zeta potentials measurements indicated that patching was the dominant mechanism under acidic and neutral conditions, while charge neutralization was the main mechanism under alkaline condition. On this basis, the chosen flocculant CS-g-PDBC was employed to treat the actual oily wastewater. Results showed that the removal ratio of both turbidity and oil exceeded 98%, suggesting that this newly synthesized CS-g-PDBC would be a promising flocculant for emulsified oily wastewater treatment.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
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2017
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IF 2.552
Jiankun Huang,Huie Liu,Shuang Chen,Chuanqin Ding
Cork-like graphene aerogels were synthesized via EDA-ammonia double hydrothermal reduction approach. The synthesized porous aerogels displayed high porosity, hydrophobicity and excellent mechanical properties. Its adsorption efficiency for oil is significantly higher than that of conventional adsorbents, having oil capacity (130.10 g/g) for pure diesel and continuous treatment capacity (71.67 g/g) for emulsified oil in oil-contaminated water. Besides, its recycling performance was evaluated by mechanical extrusion, ethanol washing and calcined regeneration, and for emulsified oil, the adsorption process follows a pseudo-second-order kinetic model and adsorption isotherms are related well by the Freundlich model with a determination coefficient. ( R 2 ) of 0.9994. Furthermore, a continuous aerogel-based water treatment process has been proposed to make the graphene-based aerogels have great potential applications for oil spill clean-up and water purification.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 6
·6153-6166
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IF 2.914
Lü Ting,Qi Dongming,Zhang Dong,Zhang Chuan,Zhao Hongting
Versatile polyethyleneimine (PEI)-coated Fe 3 O 4 magnetic nanoparticles (MNPs) have been synthesized by a one-step solvothermal method. The morphologies, structures, and properties of MNPs prepared for different reaction times have been characterized through various techniques. The synthesized MNPs were then used to separate emulsified oil and cationic and anionic heavy metal ions from the aqueous environment; moreover, the effects of the temperature, pH, and ionic strength of aqueous media, the solvothermal reaction time, and the number of reuse cycles on the removal efficiency have been investigated in detail. The results showed that pseudo-second-order kinetics and the Langmuir isotherm well described the adsorption processes of Cu(II) and Cr(VI). The Langmuir model yielded maximum adsorption capacities of 66.6 mg g −1 for Cu(II) and 54.5 mg g −1 for Cr(VI) at pH 5.0 and 25 °C. The synthetic MNPs could also efficiently separate diesel oil or olive oil droplets stabilized by sodium dodecyl sulfate from aqueous media. Moreover, these MNPs could be recycled five times without showing significant loss in separation efficiency. Notably, the synthesized PEI-coated MNPs could simultaneously separate emulsified oil and cationic and anionic heavy metal ions from multicomponent wastewater. Such versatile PEI-coated MNPs displayed good affinity towards emulsified oil and cationic and anionic heavy metal ions, showing great potential for practical applications in the treatment of complicated industrial wastewater matrices.
Simultaneous separation of emulsified oil and cationic and anionic heavy metal ions from aqueous media by using polyethyleneimine-coated Fe 3 O 4 magnetic nanoparticles.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Ao Sun,Yingqing Zhan,Ximin Chen,Hongshan Jia,Fei Zhu,Chunxia Zhao,Yinlong Li,Hui He,Yuanpeng Wu,Tian He,Tingting Hu
Membrane separation technique offers unique advantages for treating the emulsified oily wastewater with the oil droplet diameter less than 20 µm. However, the complicated membrane fouling originating from oils and soluble matters pose the huge challenges to membrane separation technique, which has stimulated the development of advanced membrane materials. Herein, we reported the photocatalytic and super-wetting poly (arylene ether nitrile) (PEN) fibrous composite membrane with high permeability and enhanced anti-fouling ability. The nitrogen-doped Bi 2 O 2 CO 3 (N-Bi 2 O 2 CO 3 ) was prepared by low-temperature chemical modification method and modified by dopamine (DA)-polyethyleneimine (PEI), which was further self-assembled on porous PEN support backbone. The hydrophilicity provided by the cross-linking reaction between PDA and PEI and micro-/nano- rough surface constructed by the flower-like N-Bi 2 O 2 CO 3 contributed to the super wetting properties (WCA=0°, UOCA>150°), which imparted the membrane with ultra-low oil adhesion. In particular, the arrangement of flower-like N-Bi 2 O 2 CO 3 effectively regulated the water channel of membrane, further increasing the permeate flux. Therefore, the fibrous composite membranes showed superior separation flux (632.79–762.81 L·m −2 ·h −1 ) and separation efficiency (>99.16%) for various oil-in-water emulsions, even under harsh conditions (90 ℃ and 2 M NaCl solution). More importantly, the N-Bi 2 O 2 CO 3 rendered the membrane excellent degradation rates for various dyes (MO: 95.53%, MeB : 96.40%, CV: 96.45%, CR: 87.14%), achieving favorable photocatalytic self-cleaning ability. This work opens an alternative strategy to fabricate fibrous composite membrane with synergistically enhanced anti-fouling for the treating complicated emulsified oily wastewater in petrochemical industry .
研究领域:
材料科学
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环境工程
·
化学工程
✓ 已验证
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2017
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IF 2.659
Ming Duan,Zipei Xu,Yali Zhang,Shenwen Fang,Xianyu Song,Yan Xiong
Core-shell magnetic and thermosensitive composite nanoparticles, named as M-DMEA, were prepared by grafting polyoxyalkylated N , N -dimethylethanolamine onto magnetite (Fe 3 O 4 ) nanoparticles. A series of characterizations were performed to figure out the properties of the as-prepared M-DMEA. The results reveal that the M-DMEA is superparamagnetic and has irregular shape with a core-shell structure. The flocculation performance of M-DMEA in oily wastewater produced from flooding (OWPF) treatment was investigated for the first time. It was found that the M-DMEA could separate emulsified oil droplets from OWPF rapidly under an external magnetic field with high oil removal (92.3% at the dosage of 2.5 g/L) at 65 °C. Moreover, due to its excellent magnetic response, the M-DMEA can be collected and recycled for another 3 cycles. Factors affecting the flocculation performance were discussed in detail. It is anticipated that as-prepared M-DMEA might find its potential application in practical oily wastewater treatment.
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
危险品化学品经营许可证（带存储）