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Yuxin Suo - One of the best experts on this subject based on the ideXlab platform.

  • Controllable CO2-Responsiveness of an Oil-in-Water Emulsion by Varying the Number of Tertiary Amine Groups or the Position of the Hydroxyl Group of Tertiary Amine
    The journal of physical chemistry. B, 2019
    Co-Authors: Shanshan Dai, Peiyao Zhu, Yuxin Suo
    Abstract:

    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.

  • Controllable CO2‑Responsiveness of an Oil-in-Water Emulsion by Varying the Number of Tertiary Amine Groups or the Position of the Hydroxyl Group of Tertiary Amine
    2019
    Co-Authors: Shanshan Dai, Peiyao Zhu, Yuxin Suo
    Abstract:

    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

Dejun Sun - One of the best experts on this subject based on the ideXlab platform.

  • temperature and co2 dual responsive pickering emulsions using jeffamine m2005 modified cellulose nanocrystals
    Langmuir, 2019
    Co-Authors: Gaihuan Ren, Zengzi Wang, Xiaoyang Zheng, Yanlin Guo, Dejun Sun
    Abstract:

    Cellulose nanocrystals (CNCs) with excellent biodegradability are promising biomaterials for use as responsive Pickering emulsifiers. However, the high hydrophilicity of CNCs limits their emulsification ability. Some existing studies have utilized complicated covalent modification procedures to increase the hydrophobicity of CNCs. To simplify the modification process, we prepared hydrophobically modified CNCs (CNCs-M2005) via simple and controllable electrostatic interactions with thermosensitive M2005. The obtained CNCs-M2005 exhibited temperature and CO2 dual-responsive properties. Subsequently, stable oil/water Pickering emulsions were prepared using the partially hydrophobic CNCs-M2005 at 20 °C. However, Demulsification occurred when the temperature increased to 60 °C. This temperature-induced Demulsification resulted from the dehydration of polyethylene oxide and polypropylene oxide, causing the aggregation of the CNCs-M2005, as shown by dynamic light scattering and transmission electron microscopy experiments. In addition, Demulsification was also achieved after bubbling CO2, which was attributed to the dissociation of the partially hydrophobic CNCs-M2005. The temperature and CO2 dual-responsive biosafe Pickering emulsions open up opportunity for the design of intelligent food, cosmetic, and drug delivery systems.

  • highly effective emulsification Demulsification with a co2 switchable superamphiphile
    Journal of Colloid and Interface Science, 2016
    Co-Authors: Zengzi Wang, Jingcheng Hao, Dejun Sun
    Abstract:

    This article reports a systematic study on a highly CO2-responsive superamphiphile (D-OA) in preparation of CO2-switchable oil-in-water emulsions. The D-OA was assembled with Jeffamine D 230 and oleic acid (HOA) via electrostatic interaction, which was characterized using FT-IR, (1)HNMR, surface tension, and interfacial tension techniques. The assembled gemini-like superamphiphile D-OA was shown to have a low cmc value and adsorb quickly at the paraffin oil/water interface, decreasing the interfacial tension effectively. Highly stable O/W emulsions were obtained by mixing D-OA aqueous solution and paraffin oil. After bubbling CO2 through the stable emulsions for just 20s, quick phase separation was observed; while upon removal of CO2 by bubbling N2 at 60°C, stable emulsions were recreated. The reversible assembly and disassembly of the D-OA superamphiphile by adding or removing CO2 were considered as the cause of Demulsification and re-emulsification processes. The rapid and complete Demulsification of the system in response to CO2 addition and removal may have potential applications in emulsion-based fabrication/separation and enhanced oil recovery processes.

Xiaoyi Wang - One of the best experts on this subject based on the ideXlab platform.

  • Research on ultrasound-assisted Demulsification/dehydration for crude oil.
    Ultrasonics sonochemistry, 2019
    Co-Authors: Dan Cao, Jin Liu, Jun Gao, Xiaoyi Wang
    Abstract:

    Abstract Crude oil Demulsification and dehydration are important links in the process of crude oil exploitation, transportation, and refining. In recent years, with the development of crude oil exploitation, the content of colloid and asphaltene in crude oil has been increasing, and the properties of crude oil emulsion have become more stable. In addition, the development and application of oil recovery technology and the use of a large number of oilfield chemicals have made the composition of crude oil more complicated. The water content and salt content of oil produced fluid increase year by year, which aggravates the task of crude oil dehydration and desalination. Therefore, it is particularly important to study the Demulsification and dehydration of crude oil. In this paper. Research on ultrasound-assisted Demulsification/dehydration for crude oil in investigated. Results indicate that the Demulsification effect varies with the increase of ultrasonic radiation time, but the difference is not significant; with the increase of temperature, the effect of ultrasonic on the Demulsification of crude oil emulsion is decreased, or the advantages of ultrasonic can be fully displayed only at low temperature; ultrasonic power has a critical value, when it is lower than this critical value, ultrasonic wave acts as demulsifying agent, and with the increase of power, dehydration rate of the crude oil emulsion increases; when higher than the critical value, the separated oil and water can be re-emulsified; ultrasonic Demulsification can both shorten settling time and reduce the amount of demulsifier; ultrasound is suitable for Demulsification and dehydration of crude oil emulsions with high water content. Results also prove that chemical demulsifier has a better effect for crude oil Demulsification /dehydration than that of ultrasonic treatment alone. In addition, recent progress on ultrasonic Demulsification equipment is introduced. The purpose of this paper is to offer equipment and technical support for crude oil Demulsification/ dehydration.

Roozbeh Rafati - One of the best experts on this subject based on the ideXlab platform.

  • effect of ultrasound radiation duration on emulsification and Demulsification of paraffin oil and surfactant solution brine using hele shaw models
    Ultrasonics Sonochemistry, 2015
    Co-Authors: Hossein Hamidi, Erfan Mohammadian, Mohammad Asadullah, Amin Azdarpour, Roozbeh Rafati
    Abstract:

    Abstract Ultrasound technique is one of the unconventional enhanced oil recovery methods which has been of interest for more than six decades. However, the majority of the oil recovery mechanisms under ultrasound reported in the previous studies are theoretical. Emulsification is one of the mechanisms happening at the interface of oil and water in porous media under ultrasound. Oppositely, ultrasound is one of the techniques using in oil industry for Demulsification of oil/water emulsion. Therefore, the conditions in which emulsification becomes dominant over Demulsification under ultrasound should be more investigated. Duration of ultrasound radiation could be one of the factors affecting emulsification and Demulsification processes. In this study a technique was developed to investigate the effect of long and short period of ultrasound radiation on emulsification and Demulsification of paraffin oil and surfactant solution in porous media. For this purpose, the 2D glass Hele-shaw models were placed inside the ultrasonic bath under long and short period of radiation of ultrasound. A microscope was used above the model for microscopic studies on the interface of oil and water. Diffusion of phases and formation of emulsion were observed in both long and short period of application of ultrasound at the beginning of ultrasound radiation. However, by passing time, Demulsification and coalescence of brine droplets inside emulsion was initiated in long period of ultrasound application. Therefore, it was concluded that emulsification could be one of the significant oil recovery mechanisms happening in porous media under short period of application of ultrasound.

Shanshan Dai - One of the best experts on this subject based on the ideXlab platform.

  • Controllable CO2-Responsiveness of an Oil-in-Water Emulsion by Varying the Number of Tertiary Amine Groups or the Position of the Hydroxyl Group of Tertiary Amine
    The journal of physical chemistry. B, 2019
    Co-Authors: Shanshan Dai, Peiyao Zhu, Yuxin Suo
    Abstract:

    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.

  • Controllable CO2‑Responsiveness of an Oil-in-Water Emulsion by Varying the Number of Tertiary Amine Groups or the Position of the Hydroxyl Group of Tertiary Amine
    2019
    Co-Authors: Shanshan Dai, Peiyao Zhu, Yuxin Suo
    Abstract:

    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