The main advantages of the use of ionic liquids in enhanced oil recovery are their tunability and stability in harsh environmental conditions. In this work, a comprehensive review of ionic liquids proposed to improve ...The main advantages of the use of ionic liquids in enhanced oil recovery are their tunability and stability in harsh environmental conditions. In this work, a comprehensive review of ionic liquids proposed to improve current chemical oil recovery methods has been presented, focusing on core flooding experiments. With an almost infinite number of possible ionic liquids, the amount of experiments carried out up to now has been very limited. However, results are promising, with additional recovery after secondary flooding of up to 32% of the original oil in place. Most formulations with ionic liquids have been proposed for sandstone reservoirs, the number of studies with carbonate cores being very scarce. The possibilities of a new room temperature surface active ionic liquid, 1-decyl-3-methylimidazolium triflate,for this application were analyzed. It was shown that it is able to drastically reduce the water/oil interfacial tension. An optimized formulation was proposed for carbonate reservoirs. After secondary flooding with brine, an additional recovery of 10.5% of original oil in place was achieved at room conditions. A combination of the proposed method followed by a polymer flooding step with polyacrylamide led to a lesser but still significant recovery, reducing the costs associated to the ionic liquid.展开更多
In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobari...In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobaric vapor–liquid equilibrium(VLE) for the quaternary system TBA + water + propane-1,3-diol + [emim]Cl at 101.3 kPa, and found the VLE data to be well correlated with the nonrandom two-liquid model. These results show that the mixed solvent of propane-1,3-diol + [emim]Cl can increase the relative volatility of TBA to water and break the azeotropic point. We found no notable synergetic effect between them, and observed that the liquid mixed solvent of propane-1,3-diol and [emim]Cl had lower viscosity than [emim]Cl, which makes it a promising entrainer for separating the TBA + water azeotrope in industrial applications.展开更多
This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) metho...This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) methods are respectively used to obtain the stable structure of the gas phase ion pair at the 6-311++G(d, p) basis set level. The theoretical IR spectra of [EMIM]+[PF6]- were obtained from the calculated vibrational frequencies and intensities. The changes of atomic charge population have been investigated using Natural Bond Orbital (NBO) analysis. The computational results show that there may exist hydrogen bonds between the cation and the anion. After ZPE and BSSE corrections, the interaction energy between the cation and the anion is –314.44 kJ?mol-1.展开更多
This study aims at investigating the impact of ionic liquid extraction on lignin structure by studying the mechanism of lignin depolymerization in 1-ethyl-3-methylimidazolium acetate EMIM[OAc]) and comparing it with t...This study aims at investigating the impact of ionic liquid extraction on lignin structure by studying the mechanism of lignin depolymerization in 1-ethyl-3-methylimidazolium acetate EMIM[OAc]) and comparing it with that of organosolv and milled wood methods. Ionic liquid mediated lignin (ILL) using EMIM[OAc]), ethanol organosolv lignin (EOL) and milled wood lignin (MWL) were isolated from Typha capensis (TC) and subjected to several analytical characterizations. Experimental data shows that ILL exhibited a relatively lower degree of condensation, lower aromatic C-C structures and a higher aliphatic OH with values of 0.42/Ar, 1.94/Ar and 1.33/Ar moieties compared with EOL values of 0.92/Ar, 2.22/Ar and 0.51/Ar moieties respectively. The ILL was depolymerized under mild conditions giving relatively higher β-aryl ether linkages content, higher molecular mass, and exhibited closer structures and reactivity to native lignin than EOL. These insights on TC lignin depolymerization in EMIM[OAc]) acetate may contribute to better value-addition of lignocellulosic biomass.展开更多
Poly[2,2-(m-phenylene)-5,5-bibenzimidazole](mPBI)were synthesized by mixing 3,3',4,4'-tetraaminobiphenyl and isophthalic acid in 1-butyl-3-methylimidazolium chloride([BMIM]Cl).Intrinsic viscosity of mPBI polym...Poly[2,2-(m-phenylene)-5,5-bibenzimidazole](mPBI)were synthesized by mixing 3,3',4,4'-tetraaminobiphenyl and isophthalic acid in 1-butyl-3-methylimidazolium chloride([BMIM]Cl).Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96%sulfuric acid.The polymer was characterized by Fourier transform infrared spectroscopy(FTIR),nuclear magnetic resonance(1H-NMR),and thermogravimetric analysis(TGA).The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated.It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature.Comparison of structure and properties of mPBI synthesized in ionic liquids(ILs)and polyphosphoric acid was also reported.It indicates that the ionic liquids are a kind of good solvents in synthesis process of mPBI and ionic liquids mainly affect molecular weight of mPBI.展开更多
A highly selective synthesis of 2,6-dimethylnaphthanlene（2,6-DMN） by transalkylation between 2-methylnaphthanlene（2-MN） and 1,2,4,5-tetramethylbenzene（TeMB） was performed with 1-alkyl-3-methylimidazo- lium alumi...A highly selective synthesis of 2,6-dimethylnaphthanlene（2,6-DMN） by transalkylation between 2-methylnaphthanlene（2-MN） and 1,2,4,5-tetramethylbenzene（TeMB） was performed with 1-alkyl-3-methylimidazo- lium aluminum chloride（[Cnmim]Cl-AlCl3） ionic liquids（ILs） as catalysts. The influences of the alkyl group as the organic cation, the acidic strength of [C4mim]Cl-AlCl3 ILs as well as the reaction conditions on the catalytic performance were investigated. [C4mim]Cl-AlCl3 ILs[x（AlCl3）=71%] exhibited high activity and selectivity toward 2,6-DMN. The selectivity to 2,6-DMN and the 2,6-DMN/2,7-DMN ratio reached up to 68.2% and 3.7：1, respectively. The UV-Vis spectrum of TeMB treated by different ILs shows that the protonated degree of TeMB dependeds on the acidity strength of ILs, which has a significant impact on the reaction results. The high protonated degree of TeMB is advantageous to enhancing the conversion of transalkylation and the large stereo-hindrance effect of TeMB is favorable to improving the selecivity to 2,6-DMN.展开更多
In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactered by the X-ray diffraction and scanning electron micrographs. The ...In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactered by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much.展开更多
This scale-up study demonstrated the feasibility of an ionic liquid(IL)pretreatment process at 40 kg scale,using the IL 1-ethyl-3-methylimidazolium acetate([C2C1Im][OAc])as the solvent.The pretreatment was followed by...This scale-up study demonstrated the feasibility of an ionic liquid(IL)pretreatment process at 40 kg scale,using the IL 1-ethyl-3-methylimidazolium acetate([C2C1Im][OAc])as the solvent.The pretreatment was followed by enzymatic hydrolysis through which the process efficiency for biomass conversion to monomeric sugars was determined.The results show that 43 wt%of switchgrass was dissolved in IL after 2 h of pretreatment at 160℃ with 15 wt%solid loading.A 120 h enzymatic hydrolysis of the pretreated switchgrass results in 96%glucan and 98%xylan conversion.[C2C1Im][OAc]pretreatment has been successfully scaled up to 40 kg with improved sugar titers and yields relative to bench scale(6 kg).The mass flow of the overall process was established and the major scale-up challenges of the process were identified.展开更多
The polyoxometalate-imidazole ionic liquids（POM-ILs） with low melting points at 94.5 and 95.5 ℃, [Cn mim]a[MosO26]（Cn mim=1-alkyl-3-methylimidazolium, n=12,14）, have been successfully synthesized and characterize...The polyoxometalate-imidazole ionic liquids（POM-ILs） with low melting points at 94.5 and 95.5 ℃, [Cn mim]a[MosO26]（Cn mim=1-alkyl-3-methylimidazolium, n=12,14）, have been successfully synthesized and characterized by DSC, single-crystal X-ray diffraction and TGA, etc. The two POM-ILs have relatively high stability with decomposing temperature up to about 347 and 344 ℃, respectively. Further photocatalytic performance was measured via the degradation of rhodamine B（RB） in aqueous solution. The experiments show that the conversion reached to 90% after 90 min under UV-light and the degradation efficiency depended on pH value, different dosages and so on. In addition, the catalysts can be recycled for several times without significant loss of activity.展开更多
A new type of polymerizable ionic liquid （IL） 1-（3-aminobenzyl）-3-methylimidazolium chloride （AMIC） was synthesized to obtain a novel polymer salt poly（1-（3-aminobenzyl）-3-methylimidazolium chloride） （PAMIC...A new type of polymerizable ionic liquid （IL） 1-（3-aminobenzyl）-3-methylimidazolium chloride （AMIC） was synthesized to obtain a novel polymer salt poly（1-（3-aminobenzyl）-3-methylimidazolium chloride） （PAMIC）. The AMIC was structurally characterized by mass spectrometry and Fourier transform infrared spectrometry （FTIR）. The structure, morphology and properties of PAMIC were investigated by FTIR, ultraviolet visible absorption spectra （UV-Vis）, scanning electron microscopy （SEM）, energy dispersive X-ray spectroscopy （EDX）, conductivity measurement and thermo- gravimetric analysis （TGA）. The PAMIC was spherulitic with an average diameter of about 50 nm and showed high conductivity and excellent thermal stability.展开更多
基金the Ministry of Science and Innovation and State Research Agency for financial support throughout project PGC2018-097342-B-I00, including European Regional Development Fund。
文摘The main advantages of the use of ionic liquids in enhanced oil recovery are their tunability and stability in harsh environmental conditions. In this work, a comprehensive review of ionic liquids proposed to improve current chemical oil recovery methods has been presented, focusing on core flooding experiments. With an almost infinite number of possible ionic liquids, the amount of experiments carried out up to now has been very limited. However, results are promising, with additional recovery after secondary flooding of up to 32% of the original oil in place. Most formulations with ionic liquids have been proposed for sandstone reservoirs, the number of studies with carbonate cores being very scarce. The possibilities of a new room temperature surface active ionic liquid, 1-decyl-3-methylimidazolium triflate,for this application were analyzed. It was shown that it is able to drastically reduce the water/oil interfacial tension. An optimized formulation was proposed for carbonate reservoirs. After secondary flooding with brine, an additional recovery of 10.5% of original oil in place was achieved at room conditions. A combination of the proposed method followed by a polymer flooding step with polyacrylamide led to a lesser but still significant recovery, reducing the costs associated to the ionic liquid.
基金supported by the Innovation Fund of Tianjin University (No. 2010XJ-0022)
文摘In this study, we used a mixture of organic liquid propane-1,3-diol and ionic liquid 1-ethyl-3-methylimidazolium chloride([emim]Cl) as the entrainer to separate tert-butyl alcohol(TBA) + water. We measured the isobaric vapor–liquid equilibrium(VLE) for the quaternary system TBA + water + propane-1,3-diol + [emim]Cl at 101.3 kPa, and found the VLE data to be well correlated with the nonrandom two-liquid model. These results show that the mixed solvent of propane-1,3-diol + [emim]Cl can increase the relative volatility of TBA to water and break the azeotropic point. We found no notable synergetic effect between them, and observed that the liquid mixed solvent of propane-1,3-diol and [emim]Cl had lower viscosity than [emim]Cl, which makes it a promising entrainer for separating the TBA + water azeotrope in industrial applications.
基金This work was supported by the National Natural Science Key Foundation of China (20490209) and Young Teacher Foundation of Beijing University of Chemical Technology (QN0308)
文摘This paper reports the ab initio and Density Functional Theory (DFT) studies on the structure of the ionic liquid 1-ethyl-3-methylimidazolium hexafluorophosphate ([EMIM]+[PF6]-). Hartree-Fock (HF) and DFT(B3LYP) methods are respectively used to obtain the stable structure of the gas phase ion pair at the 6-311++G(d, p) basis set level. The theoretical IR spectra of [EMIM]+[PF6]- were obtained from the calculated vibrational frequencies and intensities. The changes of atomic charge population have been investigated using Natural Bond Orbital (NBO) analysis. The computational results show that there may exist hydrogen bonds between the cation and the anion. After ZPE and BSSE corrections, the interaction energy between the cation and the anion is –314.44 kJ?mol-1.
文摘This study aims at investigating the impact of ionic liquid extraction on lignin structure by studying the mechanism of lignin depolymerization in 1-ethyl-3-methylimidazolium acetate EMIM[OAc]) and comparing it with that of organosolv and milled wood methods. Ionic liquid mediated lignin (ILL) using EMIM[OAc]), ethanol organosolv lignin (EOL) and milled wood lignin (MWL) were isolated from Typha capensis (TC) and subjected to several analytical characterizations. Experimental data shows that ILL exhibited a relatively lower degree of condensation, lower aromatic C-C structures and a higher aliphatic OH with values of 0.42/Ar, 1.94/Ar and 1.33/Ar moieties compared with EOL values of 0.92/Ar, 2.22/Ar and 0.51/Ar moieties respectively. The ILL was depolymerized under mild conditions giving relatively higher β-aryl ether linkages content, higher molecular mass, and exhibited closer structures and reactivity to native lignin than EOL. These insights on TC lignin depolymerization in EMIM[OAc]) acetate may contribute to better value-addition of lignocellulosic biomass.
基金Natural Science Foundation of Shanghai,China(No.09ZR1401500)
文摘Poly[2,2-(m-phenylene)-5,5-bibenzimidazole](mPBI)were synthesized by mixing 3,3',4,4'-tetraaminobiphenyl and isophthalic acid in 1-butyl-3-methylimidazolium chloride([BMIM]Cl).Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96%sulfuric acid.The polymer was characterized by Fourier transform infrared spectroscopy(FTIR),nuclear magnetic resonance(1H-NMR),and thermogravimetric analysis(TGA).The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated.It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature.Comparison of structure and properties of mPBI synthesized in ionic liquids(ILs)and polyphosphoric acid was also reported.It indicates that the ionic liquids are a kind of good solvents in synthesis process of mPBI and ionic liquids mainly affect molecular weight of mPBI.
基金Supported by the National Natural Science Foundation of China(No.21076065)the Natural Science Foundation of Heilongjiang Province of China(No.ZD200820-02)the Science&Technology Research Foundation of Education Bureau of Heilongjiang Province,China(No.11531266)
文摘A highly selective synthesis of 2,6-dimethylnaphthanlene（2,6-DMN） by transalkylation between 2-methylnaphthanlene（2-MN） and 1,2,4,5-tetramethylbenzene（TeMB） was performed with 1-alkyl-3-methylimidazo- lium aluminum chloride（[Cnmim]Cl-AlCl3） ionic liquids（ILs） as catalysts. The influences of the alkyl group as the organic cation, the acidic strength of [C4mim]Cl-AlCl3 ILs as well as the reaction conditions on the catalytic performance were investigated. [C4mim]Cl-AlCl3 ILs[x（AlCl3）=71%] exhibited high activity and selectivity toward 2,6-DMN. The selectivity to 2,6-DMN and the 2,6-DMN/2,7-DMN ratio reached up to 68.2% and 3.7：1, respectively. The UV-Vis spectrum of TeMB treated by different ILs shows that the protonated degree of TeMB dependeds on the acidity strength of ILs, which has a significant impact on the reaction results. The high protonated degree of TeMB is advantageous to enhancing the conversion of transalkylation and the large stereo-hindrance effect of TeMB is favorable to improving the selecivity to 2,6-DMN.
文摘In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactered by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much.
基金the funding support from The Bioenergy Technologies Office (BETO) within the US DOE’s Office of Energy Efficiency and Renewable Energythe funding support from the American Recovery and Reinvestment Actsupported by the US DOE’s Office of Science, Biological and Environmental Research program through contract DE-AC02-05CH11231 between Lawrence Berkeley National Laboratory and the U.S. Department of Energy
文摘This scale-up study demonstrated the feasibility of an ionic liquid(IL)pretreatment process at 40 kg scale,using the IL 1-ethyl-3-methylimidazolium acetate([C2C1Im][OAc])as the solvent.The pretreatment was followed by enzymatic hydrolysis through which the process efficiency for biomass conversion to monomeric sugars was determined.The results show that 43 wt%of switchgrass was dissolved in IL after 2 h of pretreatment at 160℃ with 15 wt%solid loading.A 120 h enzymatic hydrolysis of the pretreated switchgrass results in 96%glucan and 98%xylan conversion.[C2C1Im][OAc]pretreatment has been successfully scaled up to 40 kg with improved sugar titers and yields relative to bench scale(6 kg).The mass flow of the overall process was established and the major scale-up challenges of the process were identified.
基金Supported by the National Natural Science Foundation of China(Nos20731002, 10876002)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No200800070015)+2 种基金the Program of Cooperation of the Beijing Education Commission, China(No20091739006)the Program of Cooperation of the Beijing Technology Commission, China(No Z09010300820902)the Program for New Century Excellent Talents in University of China
文摘The polyoxometalate-imidazole ionic liquids（POM-ILs） with low melting points at 94.5 and 95.5 ℃, [Cn mim]a[MosO26]（Cn mim=1-alkyl-3-methylimidazolium, n=12,14）, have been successfully synthesized and characterized by DSC, single-crystal X-ray diffraction and TGA, etc. The two POM-ILs have relatively high stability with decomposing temperature up to about 347 and 344 ℃, respectively. Further photocatalytic performance was measured via the degradation of rhodamine B（RB） in aqueous solution. The experiments show that the conversion reached to 90% after 90 min under UV-light and the degradation efficiency depended on pH value, different dosages and so on. In addition, the catalysts can be recycled for several times without significant loss of activity.
基金financially supported by the Hunan Provincial Natural Science Foundation of China(Nos.11JJ3015 and 11JJ1009)
文摘A new type of polymerizable ionic liquid （IL） 1-（3-aminobenzyl）-3-methylimidazolium chloride （AMIC） was synthesized to obtain a novel polymer salt poly（1-（3-aminobenzyl）-3-methylimidazolium chloride） （PAMIC）. The AMIC was structurally characterized by mass spectrometry and Fourier transform infrared spectrometry （FTIR）. The structure, morphology and properties of PAMIC were investigated by FTIR, ultraviolet visible absorption spectra （UV-Vis）, scanning electron microscopy （SEM）, energy dispersive X-ray spectroscopy （EDX）, conductivity measurement and thermo- gravimetric analysis （TGA）. The PAMIC was spherulitic with an average diameter of about 50 nm and showed high conductivity and excellent thermal stability.
