In the heterogeneous reservoirs,CO_(2) flooding easily leads to CO_(2) gas channeling,which can seriously affect sweeping efficiency and reduce oil recovery.After thoroughly investigating the advantages and shortcomin...In the heterogeneous reservoirs,CO_(2) flooding easily leads to CO_(2) gas channeling,which can seriously affect sweeping efficiency and reduce oil recovery.After thoroughly investigating the advantages and shortcomings of various CO_(2) plugging technologies,this paper focuses on the feasibility of improving conventional water-alternating gas(WAG)through CO_(2)-responsive gel materials.Based on the different chemical reaction mechanisms between the unique chemical structure and CO_(2),changes in the material’s physical and chemical properties can respond to CO_(2).The feasibility of utilizing these property changes for CO_(2)-responsive plugging is explored.Various CO_(2)-responsive gels and gel nanoparticles have been extensively researched in different fields,such as energy,medicine,and biology.This paper surveys the molecular structures,chemical compositions,response mechanisms,and changes of these CO_(2)-responsive gels,aiming to draw insights into the carbon dioxide-enhanced oil recovery(CO_(2)-EOR)field.Finally,the key issues and future development direction of CO_(2)-responsive plugging gels were analyzed.展开更多
Because switchable water is difficult to apply directly for oil removal,an enhanced approach to improve oil removal is proposed using a surfactant-free microemulsion(SFME)containing switchable water.The SFME is formed...Because switchable water is difficult to apply directly for oil removal,an enhanced approach to improve oil removal is proposed using a surfactant-free microemulsion(SFME)containing switchable water.The SFME is formed using switchable water(aqueous N,N-dimethylethanolamine(DMEA)or N,N-dimethylbutylamine(BDEA))and a hydrophobic amine(N-butyldiethanolamine(DMBA)).The single-phase region for preparing the SFME is determined using a ternary phase diagram,and the microstructure types are distinguished using the con-ductivity method.The pH changes and dynamic laser scattering test results demonstrate that the SFME exhibits irreversible transformation behavior regulated by CO_(2).Moreover,the recovered SFME containing BDEA has a microstructure with a smaller particle size after removing the CO_(2) by bubbling N 2 at 65°C,which is attributed to the higher proportion of DMEA than that of BDEA.In addition,dodecane and diesel oil are shown to dissolve in the SFME,and the oil solubility of the SFME increases with increasing oil phase(DMBA)content.The interface free energy theory reveals that the oil is more easily detached with the addition of SFME than with switchable water only owing to the reduced interface free energy of oil on the solid surface.Thus,an enhanced approach for removing oil is proposed to wash oil sands,where the oil removal efficiency of switchable water can be improved by using SFMEs containing switchable water.展开更多
Environment friendly and intelligent surfactants have attracted great attention in recent years.A bio-based CO_(2)responsive surfactant rosin acid dimaleimide choline(R-BMI-C)with an extremely rigid skeleton was prepa...Environment friendly and intelligent surfactants have attracted great attention in recent years.A bio-based CO_(2)responsive surfactant rosin acid dimaleimide choline(R-BMI-C)with an extremely rigid skeleton was prepared using rosin and choline as raw materials by Diels-Alder addition reaction and acid-base neutralization reactions.Its structure was confirmed by IR and^(1)H NMR spectra.The foams’properties of R-BMI-C could be adjusted by bubbling CO_(2)/N_(2)to change the structure of the surfactant.At pH 10.4,R-BMI-C forms an unstable foam with a half-life of 1.5 h.When the pH was reduced to 7.4 by bubbling CO_(2),R-BMI-C forms an extremely stable foam with a half-life of 336 h.The surfactant R-BMI-C changed from bola type to conventional type when bubbling CO_(2).And the internal aggregation structure of R-BMI-C aqueous solution changed from spherical micelles to laminar micelles according to the cryogenic-transmission electron microscope.We know that the lamellar structure tends to adsorb at the air/water interface or is trapped in the foam film,which slows down the foam coarsening and agglomeration process,resulting in a significant increase in foam stability.R-BMI-C could be used in oil extraction,fire-fighting and chemical decontamination due to its excellent foaming,stabilization and defoaming properties.展开更多
Polymerization-induced chiral self-assembly(PICSA)is an efficient strategy that not only allows the construction of the supramolecular chiral assemblies in a controlled manner but also can regulate the morphology in s...Polymerization-induced chiral self-assembly(PICSA)is an efficient strategy that not only allows the construction of the supramolecular chiral assemblies in a controlled manner but also can regulate the morphology in situ.Herein,a series of azobenzene-containing block copolymer(Azo-BCP)assemblies with tunable morphologies and supramolecular chirality were obtained through the PICSA strategy.The supramolecular chirality of Azo-BCP assemblies could be regulated by carbon dioxide(CO_(2))stimulus,and completely recovered by bubbling with Ar.A reversible morphology transformation and chiroptical switching process could also be achieved by the alternative 365 nm UV light irradiation and heatingcooling treatment.Moreover,the supramolecular chirality is thermo-responsive and a reversible chiral-achiral switching was successfully realized,which can be reversibly repeated for at least five times.This work provides a feasible strategy for constructing triple stimuli-responsive supramolecular chiral nano-objects in situ.展开更多
基金Supported by the Open Fund Project of Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(YQZC202105)Yangtze University Student Innovation Program(Yz2022018).
文摘In the heterogeneous reservoirs,CO_(2) flooding easily leads to CO_(2) gas channeling,which can seriously affect sweeping efficiency and reduce oil recovery.After thoroughly investigating the advantages and shortcomings of various CO_(2) plugging technologies,this paper focuses on the feasibility of improving conventional water-alternating gas(WAG)through CO_(2)-responsive gel materials.Based on the different chemical reaction mechanisms between the unique chemical structure and CO_(2),changes in the material’s physical and chemical properties can respond to CO_(2).The feasibility of utilizing these property changes for CO_(2)-responsive plugging is explored.Various CO_(2)-responsive gels and gel nanoparticles have been extensively researched in different fields,such as energy,medicine,and biology.This paper surveys the molecular structures,chemical compositions,response mechanisms,and changes of these CO_(2)-responsive gels,aiming to draw insights into the carbon dioxide-enhanced oil recovery(CO_(2)-EOR)field.Finally,the key issues and future development direction of CO_(2)-responsive plugging gels were analyzed.
基金supported by the Sichuan Province Fund for Distin-guished Young Scholars in China.(No.2019JDJQ0047)Applied Basic Research Project of Sichuan Provincial Department of Science and Tech-nology(No.2020YJ0343)Chengdu Science and Technology Project of the Chengdu Bureau of Science and Technology(2021-YF05-00194-SN).
文摘Because switchable water is difficult to apply directly for oil removal,an enhanced approach to improve oil removal is proposed using a surfactant-free microemulsion(SFME)containing switchable water.The SFME is formed using switchable water(aqueous N,N-dimethylethanolamine(DMEA)or N,N-dimethylbutylamine(BDEA))and a hydrophobic amine(N-butyldiethanolamine(DMBA)).The single-phase region for preparing the SFME is determined using a ternary phase diagram,and the microstructure types are distinguished using the con-ductivity method.The pH changes and dynamic laser scattering test results demonstrate that the SFME exhibits irreversible transformation behavior regulated by CO_(2).Moreover,the recovered SFME containing BDEA has a microstructure with a smaller particle size after removing the CO_(2) by bubbling N 2 at 65°C,which is attributed to the higher proportion of DMEA than that of BDEA.In addition,dodecane and diesel oil are shown to dissolve in the SFME,and the oil solubility of the SFME increases with increasing oil phase(DMBA)content.The interface free energy theory reveals that the oil is more easily detached with the addition of SFME than with switchable water only owing to the reduced interface free energy of oil on the solid surface.Thus,an enhanced approach for removing oil is proposed to wash oil sands,where the oil removal efficiency of switchable water can be improved by using SFMEs containing switchable water.
基金supported by the National Natural Science Foundation of China(32171734)the Scientific Research Funds of Huaqiao University(20BS201).
文摘Environment friendly and intelligent surfactants have attracted great attention in recent years.A bio-based CO_(2)responsive surfactant rosin acid dimaleimide choline(R-BMI-C)with an extremely rigid skeleton was prepared using rosin and choline as raw materials by Diels-Alder addition reaction and acid-base neutralization reactions.Its structure was confirmed by IR and^(1)H NMR spectra.The foams’properties of R-BMI-C could be adjusted by bubbling CO_(2)/N_(2)to change the structure of the surfactant.At pH 10.4,R-BMI-C forms an unstable foam with a half-life of 1.5 h.When the pH was reduced to 7.4 by bubbling CO_(2),R-BMI-C forms an extremely stable foam with a half-life of 336 h.The surfactant R-BMI-C changed from bola type to conventional type when bubbling CO_(2).And the internal aggregation structure of R-BMI-C aqueous solution changed from spherical micelles to laminar micelles according to the cryogenic-transmission electron microscope.We know that the lamellar structure tends to adsorb at the air/water interface or is trapped in the foam film,which slows down the foam coarsening and agglomeration process,resulting in a significant increase in foam stability.R-BMI-C could be used in oil extraction,fire-fighting and chemical decontamination due to its excellent foaming,stabilization and defoaming properties.
基金financial support from the National Natural Science Foundation of China(Nos.92056111 and 21971180)Nature Science Key Basic Research of Jiangsu Province for Higher Education(No.19KJA360006)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX202655)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions supported this work。
文摘Polymerization-induced chiral self-assembly(PICSA)is an efficient strategy that not only allows the construction of the supramolecular chiral assemblies in a controlled manner but also can regulate the morphology in situ.Herein,a series of azobenzene-containing block copolymer(Azo-BCP)assemblies with tunable morphologies and supramolecular chirality were obtained through the PICSA strategy.The supramolecular chirality of Azo-BCP assemblies could be regulated by carbon dioxide(CO_(2))stimulus,and completely recovered by bubbling with Ar.A reversible morphology transformation and chiroptical switching process could also be achieved by the alternative 365 nm UV light irradiation and heatingcooling treatment.Moreover,the supramolecular chirality is thermo-responsive and a reversible chiral-achiral switching was successfully realized,which can be reversibly repeated for at least five times.This work provides a feasible strategy for constructing triple stimuli-responsive supramolecular chiral nano-objects in situ.
