FUEL
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2023
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IF 7.4
Liwei Shen,Tianqi Liu,Huan Li,Shuman Li,Zhijie Hu,Xuebin Jiang,Hanjun Liu,Zejun Zhang,Yuanzhu Mi,Weichu Yu
The separation of oil–water emulsions is a pressing and crucial task due to the significant impact on transportation costs and pipeline corrosion. Currently, commercially available demulsifiers mainly utilize ethylene oxide and propylene oxide as raw materials. However, these demulsifiers involve complex and hazardous production processes, exhibit low demulsification efficiency (DE), and require high temperatures exceeding 60 °C. To address these challenges, this study presents a two-step synthesis method for producing a demulsifier (PDB-C6) that resembles a jellyfish. This demulsifier demonstrates a high DE in demulsification processes, operating at lower temperatures and shorter timeframes. Its hydrophilic head can locate water droplets in the emulsions, while the four hydrophobic tails can assist its rapid migration in the oil phase towards the oil–water interface for demulsification. The demulsifying performance was investigated in two W/O emulsions with different oil contents. Bottle tests showed that the DE of PDB-C6 in a 30% oil content W/O emulsion reached 100% with the dosage of 300 mg/L at 40 °C for 2 h, while the dosage of 400 mg/L for 3 h also achieved 100% of DE in a 70% oil content W/O emulsion. In addition, PDB-C6 had excellent demulsification performance in both high salinity and a wide pH range (2–12). Given its low demulsifier amount, low demulsification temperature, short demulsification time and high DE, PDB-C6 shows promise for wide-ranging applications in the petroleum industry. The impacts of PDB-C6 on the oil–water interface were systematically investigated and its possible demulsification mechanism in W/O emulsions was explored in detail. The findings revealed that PDB-C6 had excellent demulsification performance by rapidly migrating to the oil–water interface where it replaced natural surfactant and formed an unstable composite membrane, ultimately reducing the stability of the emulsion and leading to demulsification.
研究领域:
化学工程
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石油工程
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产品关联
DOI
高影响因子
Journal of CO2 Utilization
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2018
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IF 5.503
Shuai Wang,Dongfang Liu,Jihe Zhao,Xiaojiang Li,Daixue Xu,Yuan Gu,Hongsheng Lu
In this paper, a practical and environmental friendly method was successfully developed by using CO 2 -Triggered switchable water additive to reversibly emulsify and demulsify diesel, aims to provide guidance for recovering oil substances in waste oil-based drill cuttings. In this new method, N, N, N', N'-tetramethyl-1, 6-hexanediamine(TMHDA) was a switchable water additive whose aqueous solution can switch the ionic strength by addition and removal CO 2 . Then it can be used to separate diesel through reversibly emulsification and demulsification. The nuclear magnetic resonance hydrogen spectrum ( 1 H NMR) and conductivity demonstrated TMHDA have better switching performance. Then, diesel/naphthenic acid mixtures have been used for modeling the application of recovering oil substances in waste oil-based drill cuttings. When the acid value≥1.76mgKOH/g (the oil and TMHDA solution were 5 mL), diesel can be emulsified. The material produced by TMHDA and naphthenic acid have a strong surface activity so that the oil/water interfacial tension was less than 0.1 mN·m −1 . The demulsification performance was illustrated by change of the ionic strength, pH and the content of oil in the aqueous phase during the breaking process. Brief provided two optimization strategies of recycling of TMHDA additive. Finally, the possible mechanism of the new method was discussed.
研究领域:
环境科学
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化学工程
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产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2023
·Vol. 33
·期 43
·2304459
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IF 19
Haoyu Dai,Linfeng Yang,Yaping Feng,Junhan Sun,Fenglin Chen,Xianfeng Luo,Zengyi He,Xuetao Xu,Bing Wang,Xubo Liu,Zhichao Dong,Lei Jiang
Emulsified oil leakage onto the bulk water surface causes severe issues on global ecology and health. Developing efficient, rapid, and universal separation methods of emulsions has been a significant topic in scientific studies. However, a contactless and additive-free strategy to achieve continuous floating emulsion separation and oil collection remains to be discovered. Herein, a universal contactless demulsification, transportation, and collection method to dispose floating emulsions by ionic wind, which contains active charged particles generated by corona discharge is reported. The splash-like demulsification process of floating emulsions is attributed to the rupture of water film enveloped on oil droplet surface, simultaneously and respectively. The evidence of this process recorded by a high-speed camera with 20 000 fps has a referential significance for other works. This study may clean up universal floating emulsions discharged on water in real situations such as oil stations, chemical plants, and restaurants, and furthermore increase the potential of remote control in liquid dynamics by corona discharge.
研究领域:
环境科学
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流体力学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2024
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IF 5.3
Lingrui Chen,Wen Xu,Ji’an He,Xuemin Yan,Lu Lai,Weichu Yu,Yuanzhu Mi,Huan Li
Traditional demulsifiers are commonly produced using raw materials like ethylene oxide and propylene oxide, which deplete significant petroleum resources and involve hazardous and complex manufacturing processes. In this investigation, a hydrophobically modified chitosan (HMC) was synthesized by grafting dodecyl diethanolamine onto natural chitosan to facilitate the separation of O/W emulsions. Characterization of HMC was conducted using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance hydrogen spectroscopy ( 1 H NMR) and scanning electron microscopy (SEM). The demulsification efficacy of HMC was assessed through a bottle test in an O/W emulsion containing 0.2 % crude oil. Results showed that at a HMC dosage of 40 mg/L, the light transmission (W T ) and oil removal efficiency (W R ) of the resulted water phase were 93.4 ± 0.8 % and 99.8 ± 0.1 %, respectively. Furthermore, the competitive adsorption between natural surfactants and HMC at the interface was investigated using interfacial tension (IFT), three-phase contact angle (CA), droplet coalescence time (CTA), and interfacial film substitution. A potential demulsifying mechanism was also proposed, emphasizing HMC’s hydrophilic core and dispersed hydrophobic alkyl chains that enable rapid diffusion to the oil–water interface, replacing interfacial active components to induce demulsification by destabilizing the composite film. The advantages of HMC demulsifier over commercial demulsifiers lie in its superior environmental benefits, diverse range of sources, higher efficiency, and outstanding demulsification performance.
研究领域:
环境科学
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材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2018
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IF 6.578
Jindan Wu,Wei Wei,Shihong Li,Qi Zhong,Fu Liu,Jinhuan Zheng,Jiping Wang
The effect of membrane surface charge on demulsification and fouling resistance during emulsion separation is investigated. By grafting poly(2-dimethylaminoethyl methacrylate) (pDMAEMA) and poly(oligo(ethylene glycol) methacrylate) (pOEGMA) onto polypropylene (PP) membrane via ultraviolet (UV)-initiated polymerization, the obtained membranes PP- g -pDMAEMA and PP- g -pOEGMA present positive and negative surface charges in water, respectively. During the emulsion separation, PP- g -pOEGMA and PP- g -pDMAEMA membranes exhibit different separation efficiencies and pollutant resistant behaviors to the emulsions prepared from anionic surfactant (sodium dodecyl sulfate, SDS) and cationic surfactant (cetyltrimethylammonium bromide, CTAB). Comparing to PP- g -pOEGMA, the separation efficiency of PP- g -pDMAEMA was 15% (SDS emulsion) and 300% (CTAB emulsion) higher. But the flux recovery ratio of PP- g -pOEGMA was raised 30% (SDS emulsion) and 16% (CTAB emulsion). Hence, the membrane surface positive charges assist demulsification, but aggravate the membrane fouling . The mechanism obtained is beneficial to construct membranes with high separation efficiency and long-term durability.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
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2019
·
IF 2.923
Shanshan Dai,Peiyao Zhu,Yuxin Suo,Hongsheng Lu
A series of water-soluble tertiary amines (TAs) are introduced into an oil-in-water (O/W) emulsion stabilized by sodium oleate (NaOA). TAs convert into bicarbonate salts upon bubbling of CO2, which could induce the increase of ionic strength of the aqueous phase, form ion pairs with NaOA by electrostatic interaction, and finally result in demulsification. ζ-Potential, conductivity, pH value, 1H NMR, separation rate, and interfacial tension are applied to figure out the effects of number of tertiary amine groups and different positions of the hydroxyl group. TA with an increasing number of tertiary amine groups can further stabilize the O/W emulsion and accelerate the process of demulsification by bubbling CO2. More tertiary amine groups bring about a more stable emulsion and faster demulsification by bubbling CO2. The position of the hydroxyl group is a key factor affecting the solubility of the corresponding ion pair formed with NaOA. The better the water solubility, the slower the demulsification. The worse the water solubility of the ion pair, the more perfect the demulsification is. More importantly, water-soluble TA, with proper structure, could bring about perfect demulsification.
研究领域:
化学
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材料科学
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产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
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2022
·
IF 7.693
Lingyun Kong,Songxiang Zhu,Xiujie Quan,Yi Peng
The demulsification of emulsified asphalt is required to form the adhesion of the asphalt. Using conductivity experiments and validated molecular dynamics simulations, this paper investigated the micro-mechanism of the demulsification process of emulsified asphalt. The results show that the phenyl functional group causes a decrease in the diffusion coefficient of the SiO 2 aggregate system and an increase in its interfacial energy, whereas an inverse tendency occurs in the CaCO 3 aggregate system, which significantly affects the demulsification rate and adhesion between the emulsified asphalt and aggregates. The electrostatic force between Na + and CaCO 3 allows the emulsifiers to adsorb well to the aggregates, and the demulsification time can be controlled by adjusting the relative content of phenyl functional groups and Na + . The adsorption rate and the adsorption amount of dodecyl anion emulsified asphalt on the aggregate surface grow with increasing phenyl functional group content, leading to a faster demulsification rate of the system and enabling the demulsification rate of the SiO 2 emulsified asphalt system to be greater than that of the CaCO 3 system. This research demonstrates that the demulsification process of emulsified asphalt can potentially be adjusted by managing the relative content of Na + and phenyl functional groups in the emulsifier, which gives critical insight into improving the design and construction of asphalt pavements.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Xiaojing Li,Shouping Xu,Xinjuan Zeng,Yuanyang Yan,Min Zhang,Jie Luo,Pihui Pi,Xiufang Wen
Conventional special wettable membranes for the separation of the surfactant-stabilized oil/water emulsions primarily rely on the “size-sieving” mechanism, which enhances efficiency by reducing the pore size, leading to a trade-off between separation flux and efficiency. Inspired by spider silk, we developed a novel Janus membrane (JPSPP) capable of high demulsification capacity and constant separation flux. This membrane combines a superhydrophobic PS@PDMS membrane (PPM) with spindle-knotted structures on a negatively charged superhydrophilic PAN@SAS membrane (PSM) through electrospinning. The synergy of electrostatic force generated by charged surfaces, the Laplace pressure created by spindle-knotted geometry, and the wettability gradient resulting from asymmetric wettability enhance the demulsification capacity. The high and constant separation flux was achieved as Laplace pressure drives rapid coalescence of demulsified oil droplets towards the top of the spindle-knotted structures, facilitating oil detachment and efficient water permeation downward. As a result, the JPSPP membrane achieved a separation efficiency exceeding 99.9 %, with a constant separation flux of up to 1952.27 L m −2 h −1 , representing a 3–4 folds improvement compared to the pure PAN membranes (PM). The separation performance of the JPSPP still maintains excellent separation performance with efficiency above 98.3 % and a slight attenuation in flux after twenty filtration cycles. The research proposes groundbreaking solutions that significantly enhance the demulsification efficiency and maintain a constant separation flux for oil/water emulsions, with the potential to profoundly impact multiple industries including food processing, energy production, and the petroleum industry, etc.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
·
IF 7.312
Jingjing Zhou,Hong Sui,Jun Ma,Xingang Li,Nabil. H.A. Al-Shiaani,Lin He
Oil-water emulsions separation is a significant and intractable problem in many industrial processes, especially in petroleum industry. To deal with the demulsification of oil–water emulsions, a novel kind of amphiphilic magnetic demulsifier (M-ANP) has been designed and successfully synthesized by grafting aliphatic alcohol nonionic propylene oxide-ethylene oxide block polyether (ANP) (~22.3 mg/g) onto the surface of epoxy-functionalized magnetite (Fe 3 O 4 ) nanoparticles (~9.1 nm). The physicochemical and interfacial properties of M-ANP have been characterized and analyzed. The bottle tests show that the M-ANP performs well in fast (less than 5 min) and relatively complete demulsifying (up to 95.5%) both water-in-oil emulsions (water-in-crude oil, water-in-bitumen) and oil-in-water emulsions (diesel-in-water, crude oil-in-water, etc.) under room temperature. It also works well in breaking the stable water-in-asphaltene emulsions, achieving the demulsification efficiency of 90.0% within 2 min without heating (at 2000 ppm of M-ANP). Mechanistic study shows that the ANP and magnetic nanoparticles work synergistically in emulsions separation. The hydrophilic polyethylene oxide segments in the ANP would form hydrogen bonds with water, facilitating the interfacial adsorption of M-ANP. Furthermore, the multi-functional characteristics of magnetic nanoparticles (nano size, magnetic response and high density) promote the transfer of nanoparticles in dispersed phase and enhance the gravity settling and magnetic separation process of coalesced droplets. This kind of nanoparticle demulsifier would serve for promising applications in a variety of industrial and environmental processes at an energy-saving way.
研究领域:
化学工程
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环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
·
2019
·
IF 2.923
Ying Zhang,Dongfang Liu,Shanshan Dai,Hongsheng Lu
A novel surfactant-free microemulsion (SFME) based on CO2-induced ionic liquids (ILs) was prepared. Among them, dipropylamine (DPA) was directly reacted with CO2 to form the ILs that were composed of the ammonium salts and the ammonium carbamate salts, which was confirmed by 13C NMR, Fourier transform infrared, electrical conductivity, and pH. In addition, the purity of ILs was determined by 1H NMR. We used water as a polar phase, ILs as an amphi-solvent, and 1-dodecanol as a nonpolar phase to prepare SFME. The multiphase zone and the single-phase zone of the SFME were obtained from the ternary-phase diagram. Then, the microstructure of the studied SFME was determined to be the O/W type by the staining method. The demulsification process of SFME was explored by means of conductivity, pH, dynamic light scattering, and gas chromatography. Under the introduction of N2, CO2 could be removed, and the ILs could be reversibly restored to DPA, resulting in a change in polarity, which caused most of DPA to transfer into the oil phase, eventually leading to demulsification.
研究领域:
化学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Sciences
·
2021
·
IF 5.565
Liang Wang,Ben Zhang,Bin Zhao,Saiguo Yang,Kun Wu,Jingqiu Sun,Chengzhi Hu
Surfactants are widely used to improve the solubility of oil in water in petrochemical, making it more difficult to remove oil–water emulsions during the water treatment process. Electrocoagulation (EC) is an appropriate method for treating oily wastewater and destabilizing emulsions. However, the demulsification mechanism of oil–water droplets emulsified by surfactants with different charges have not been investigated systematically. The demulsification performance of electrocoagulation on emulsions wastewater containing cationic, non-ionic, and anionic surfactants was studied. The results showed that the removal rate of total organic carbon (TOC) in oily wastewater with anionic surfactant by EC reached 92.98% ± 0.40% at a current density of 1 mA/cm 2 , while that of the non-ionic surfactant was 84.88% ± 0.63%. The characterization of flocs showed that EC has the highest coagulation and demulsification of oil droplets with a negative charge on the surface (−70.50 ± 10.25 mV), which indicated that the charge neutralization of oil droplets was beneficial for the destabilization of the formed oily flocs. However, when the zeta potential of the oil droplets reached 75.50 ± 1.25 mV, the TOC removal efficiency was only 11.80% ± 1.43%. The TOC removal could achieve 33.23% ± 3.21% when the current density improved from 1 mA/cm 2 to 10 mA/cm 2 . The enhanced removal was due to the sweep coagulation rather than charge neutralization. This study provides a fundamental basis for the electrochemical treatment of oily wastewater.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Ning Hou,Xin Zhao,Ziyi Han,Xinxin Jiang,Yongping Fang,Yun Chen,Dapeng Li
The inability to demulsify oil-in-water emulsions via green and efficient processes is a challenging problem in many industrial processes. As a novel biodemulsifier, protein demulsifiers display excellent dispersibility and stability, but their demulsification mechanisms are not clear, which severely restricts their large-scale production and application. In this study, the demulsification mechanism of the high-efficiency protein biodemulsifier oxalate decarboxylase (Bacm OxdC), which is secreted by the Bacillus mojavensis XH1 strain, for an oil-in-water emulsion was analyzed. The results showed that Bacm OxdC was spontaneously adsorbed at the oil-water interface and turned its hydrophobic amino acids outward to increase its hydrophobicity and break the emulsified system. Furthermore, it effectively reduced the oil-water interfacial tension and interfacial film strength, thereby reducing the oil-water interfacial energy and finally enabling demulsification. To further improve the demulsification efficiency and reusability, Fe 3 O 4 @SiO 2 @OxdC-DDSA was prepared. This method provided a magnetic response for Bacm OxdC and enabled efficient demulsification. The demulsification rate of Fe 3 O 4 @SiO 2 @OxdC-DDSA reached 98.1% at 24 h, which was 30.7% higher than that of the original Bacm OxdC. After three cycles, the demulsification rate still reached 89.3%, proving it has excellent recyclability . This work is the first study on the demulsification mechanism of protein biodemulsifiers and provides useful insights into the demulsification mechanism of biodemulsifiers for oil-in-water emulsions. In addition, a promising high-efficiency modification technique for protein biodemulsifiers was proposed, which provided information for the development of biodemulsifiers for oil-water separation.
研究领域:
生物化学
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环境科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）