A novel alkanolamine-based ionic liquid,N-methyl-diethanolammonium tetrafluoroborate ([MDEA][BF4]),was synthesized in our laboratory.The ionic liquid-based composite solution consisting of N-methyl-diethanolamine (MDE...A novel alkanolamine-based ionic liquid,N-methyl-diethanolammonium tetrafluoroborate ([MDEA][BF4]),was synthesized in our laboratory.The ionic liquid-based composite solution consisting of N-methyl-diethanolamine (MDEA),[MDEA][BF4],piperazine (PZ) and H2O was investigated for CO_(2) capture.The optimal performance for CO_(2) capture was found at 45°C,1.50 MPa,probably due to a synergistic action of the reaction and the transport.No apparent corrosion was found on stainless and carbon steel with the above composite solution.This finding is very significant to the promotion of its engineering application.展开更多
To solve the inherent disadvantages in conventional processes for electrodeposition of zinc, it's necessary to develop more high-efficiency and environmentally friendly electrolytes. In this work, it was found that t...To solve the inherent disadvantages in conventional processes for electrodeposition of zinc, it's necessary to develop more high-efficiency and environmentally friendly electrolytes. In this work, it was found that the dissolution of ZnO was remarka- bly enhanced in some imidazolium chloride by the addition of urea, and the solubility of ZnO in 1:1 [Amim]C1/urea mixture was as high as 8.35 wt% at 373.2 K. Electrochemical measurements showed that zinc could be readily electrodeposited from the solutions of ZnO. Bright, dense and well adherent zinc coatings with good purity were obtained from 0.6 M solution of ZnO in 1:1 [Amim]C1/urea at 323.2-343.2 K. It's expected that the solutions of ZnO in imidazolium chloride/urea mixtures have the potential to replace the traditional electrolytes, especially toxic zinc chloride-based ones for zinc electroplating, as well as preparation of zinc materials.展开更多
With the wide application of ionic liquids(ILs)in various fields,developing efficient techniques to recover ILs from effluent is an urgent demand for the cost reduction and the environmental protection.In this study,a...With the wide application of ionic liquids(ILs)in various fields,developing efficient techniques to recover ILs from effluent is an urgent demand for the cost reduction and the environmental protection.In this study,an electrodialysis(ED)method was used to recover 1-butyl-3-methylimidazolium chloride([Bmim]Cl)IL from aqueous solution as model effluent.The influences of initial IL concentration and applied voltage on the current efficiency,removal ratio,desalination ratio,membrane flux and specific energy consumption during the ED process were investigated.It was found that the removal ratio and desalination ratio increases with the increasing of initial IL concentration and applied voltage.The current efficiency decreases with the increasing of initial IL concentration and the current efficiency reached the maximum value of 94.3%at 25 V.Besides,as the applied voltage increases,the membrane flux increases and the specific energy consumption decreases.Moreover,the fouling of cation-exchange membrane was also discovered after the desalination of IL.The deposits on the surface or into the membrane which is probably caused by[Bmim]+was characterized by scanning electron microscopy,elemental analysis and Fourier transform infrared.展开更多
Quantum chemical calculations of the structures and cation-anion interaction of 1-ethyl-3-methylimidazolium lactate ([Emim][LAC]) ion pair at the B3LYP/6-31++G** theoretical level were performed. The relevant geometri...Quantum chemical calculations of the structures and cation-anion interaction of 1-ethyl-3-methylimidazolium lactate ([Emim][LAC]) ion pair at the B3LYP/6-31++G** theoretical level were performed. The relevant geometrical characteristics, energy properties, intermolecular H-bonds (H-bonds), and calculated IR vibrations with respect to isolated ions were systematically discussed. The natural bond orbital (NBO) and atoms in molecule (AIM) analyses were also employed to understand the nature of the interactions between cation and anion. The five most stable geometries were verified by analyzing the relative energies and interaction energies. It was found that the most of the C-H···O intermolecular H-bonds interactions in five stable conformers have some covalent character in nature. The elongation and red shift in IR spectrum of C-H bonds which involve in H-bonds is proved by electron transfers from the lone pairs of the carbonyl O atom of [LAC] to the C-H antibonding orbital of the [Emim]+. The interaction modes are more favorable when the carbonyl O atoms of [LAC] interact with the C2-H of the imidazolium ring and the C-H of the ethyl group through the formation of triple H-bonds.展开更多
Ionic liquids (ILs) have been widely used in separation, catalysis, electrochemistry, etc., and one of the most outstanding characteristics is that ILs can be tailored and tuned for specific tasks. In order to design ...Ionic liquids (ILs) have been widely used in separation, catalysis, electrochemistry, etc., and one of the most outstanding characteristics is that ILs can be tailored and tuned for specific tasks. In order to design and make better use of ionic liquids, the structures and properties relationship is indispensable. Both molecular dynamics and Monte Carlo simulations have been proved useful to understand the behavior of molecules at the microscale and the properties of the system. However, the quality of such simulations depends on force field parameters describing the interactions between atoms. All-atom (AA) or the united-atom (UA) force fields will be chosen because of the demand for more exact results or the lower computational cost, respectively. In order to make a systematic comparison of the two force fields, molecular simulations for four kinds of acyclic guanidinium-based ionic liquids (cations: (R2N)2C=N+<, anion: nitric or perchloric acid) were performed based on the AA and the UA force fields in this work. AA force field parameters were derived from our previous work (Fluid Phase Equilib., 2008, 272: 1-7), and the UA parameters were proposed in this work. Molecular dynamics simulation results for the AA and UA force fields were compared. Simulation densities are very similar to each other. Center of mass radial distribution functions (RDFs), site to site RDFs and spatial distribution functions (SDFs) were also investigated to depict the microscopic structures of the ILs.展开更多
文摘A novel alkanolamine-based ionic liquid,N-methyl-diethanolammonium tetrafluoroborate ([MDEA][BF4]),was synthesized in our laboratory.The ionic liquid-based composite solution consisting of N-methyl-diethanolamine (MDEA),[MDEA][BF4],piperazine (PZ) and H2O was investigated for CO_(2) capture.The optimal performance for CO_(2) capture was found at 45°C,1.50 MPa,probably due to a synergistic action of the reaction and the transport.No apparent corrosion was found on stainless and carbon steel with the above composite solution.This finding is very significant to the promotion of its engineering application.
基金supported financially by the National Basic Research Program of China (2009CB219901)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2012BAF03B01)+1 种基金the National Natural Science Foundation of China(20906096)Open-end Fund of State Key Laboratory of Multiphase Complex Systems (MPCS-2011-D-06)
文摘To solve the inherent disadvantages in conventional processes for electrodeposition of zinc, it's necessary to develop more high-efficiency and environmentally friendly electrolytes. In this work, it was found that the dissolution of ZnO was remarka- bly enhanced in some imidazolium chloride by the addition of urea, and the solubility of ZnO in 1:1 [Amim]C1/urea mixture was as high as 8.35 wt% at 373.2 K. Electrochemical measurements showed that zinc could be readily electrodeposited from the solutions of ZnO. Bright, dense and well adherent zinc coatings with good purity were obtained from 0.6 M solution of ZnO in 1:1 [Amim]C1/urea at 323.2-343.2 K. It's expected that the solutions of ZnO in imidazolium chloride/urea mixtures have the potential to replace the traditional electrolytes, especially toxic zinc chloride-based ones for zinc electroplating, as well as preparation of zinc materials.
基金supported by the National Basic Research Program of China(973 Program)(2013CB733506)the National Natural Science Foundation of China(21036007,21076113)
文摘With the wide application of ionic liquids(ILs)in various fields,developing efficient techniques to recover ILs from effluent is an urgent demand for the cost reduction and the environmental protection.In this study,an electrodialysis(ED)method was used to recover 1-butyl-3-methylimidazolium chloride([Bmim]Cl)IL from aqueous solution as model effluent.The influences of initial IL concentration and applied voltage on the current efficiency,removal ratio,desalination ratio,membrane flux and specific energy consumption during the ED process were investigated.It was found that the removal ratio and desalination ratio increases with the increasing of initial IL concentration and applied voltage.The current efficiency decreases with the increasing of initial IL concentration and the current efficiency reached the maximum value of 94.3%at 25 V.Besides,as the applied voltage increases,the membrane flux increases and the specific energy consumption decreases.Moreover,the fouling of cation-exchange membrane was also discovered after the desalination of IL.The deposits on the surface or into the membrane which is probably caused by[Bmim]+was characterized by scanning electron microscopy,elemental analysis and Fourier transform infrared.
基金supported by the National Basic Research Program of China (2009CB219901)the National Natural Scientific Fund of China(21073194, 21106146)
文摘Quantum chemical calculations of the structures and cation-anion interaction of 1-ethyl-3-methylimidazolium lactate ([Emim][LAC]) ion pair at the B3LYP/6-31++G** theoretical level were performed. The relevant geometrical characteristics, energy properties, intermolecular H-bonds (H-bonds), and calculated IR vibrations with respect to isolated ions were systematically discussed. The natural bond orbital (NBO) and atoms in molecule (AIM) analyses were also employed to understand the nature of the interactions between cation and anion. The five most stable geometries were verified by analyzing the relative energies and interaction energies. It was found that the most of the C-H···O intermolecular H-bonds interactions in five stable conformers have some covalent character in nature. The elongation and red shift in IR spectrum of C-H bonds which involve in H-bonds is proved by electron transfers from the lone pairs of the carbonyl O atom of [LAC] to the C-H antibonding orbital of the [Emim]+. The interaction modes are more favorable when the carbonyl O atoms of [LAC] interact with the C2-H of the imidazolium ring and the C-H of the ethyl group through the formation of triple H-bonds.
基金supported by the General Program Youth of National Natural Science Foundation of China (20903098, 21073194, 21106146)State Key Laboratory of Multiphase Complex Systems (MPCS-2011-D-05)
文摘Ionic liquids (ILs) have been widely used in separation, catalysis, electrochemistry, etc., and one of the most outstanding characteristics is that ILs can be tailored and tuned for specific tasks. In order to design and make better use of ionic liquids, the structures and properties relationship is indispensable. Both molecular dynamics and Monte Carlo simulations have been proved useful to understand the behavior of molecules at the microscale and the properties of the system. However, the quality of such simulations depends on force field parameters describing the interactions between atoms. All-atom (AA) or the united-atom (UA) force fields will be chosen because of the demand for more exact results or the lower computational cost, respectively. In order to make a systematic comparison of the two force fields, molecular simulations for four kinds of acyclic guanidinium-based ionic liquids (cations: (R2N)2C=N+<, anion: nitric or perchloric acid) were performed based on the AA and the UA force fields in this work. AA force field parameters were derived from our previous work (Fluid Phase Equilib., 2008, 272: 1-7), and the UA parameters were proposed in this work. Molecular dynamics simulation results for the AA and UA force fields were compared. Simulation densities are very similar to each other. Center of mass radial distribution functions (RDFs), site to site RDFs and spatial distribution functions (SDFs) were also investigated to depict the microscopic structures of the ILs.