科创中国

Monoethanolamine fluoroborate, N-methyl-diethanolamine fluoroborate, N-methyl-diethanolamine sulfate, N-methyl-diethanolamine phosphate, and N-methyl-diethanolamine hydrochloride were synthesized to form composite absorbents to capture CO₂. The thermodynamics properties of the various systems were accurately measured. The captured CO₂ could be released very easily from the composite systems, which means less energy will be needed in the regeneration process of absorbents. CO₂ absorption and desorption mechanisms of amines and ionic liquids were also studied. Some new and reasonable mechanisms were discovered according to the characterization results of absorption systems before and after CO₂ capture. This is an abstract of a paper presented at the AIChE 2010 Spring National Meeting (San Antonio, TX 3/21-25/2010).

Yansong Zhao;香平 张;Haifeng Dong;锁江 张

2010

Simulation study of eight kinds of phosphonium-based ionic liquids (ILs) is reported in this work. Force fields for two kinds of alkoxyphosphonium ILs are proposed through systematic method and validated by the experimental densities. The study was conducted by molecular dynamics simulations. A connection between the intermolecular energy, divided into the electrostic force and the van der Waals force, and the experimental viscosities was found. Radial distribution functions (RDFs) were analyzed to probe the local organization of the liquids. First-shell coordination numbers are also reported by integral of RDFs from zero to the first minimum. In order to compare the interaction strength and position between ions for different kinds of ILs, the relative density distributions along with the distance between cation and anion are proposed. Hydrogen bond numbers were investigated to depict the microinteraction. We found that, although there are six anions in the first solvation shell of [P _2,2,2,5]⁺, only one hydrogen bond could be found. Along with increase in the length of alkyl chain, the hydrogen bond number becomes less, and no hydrogen bond interaction is found for 20% of the ions in [P _4,4,4,14][Tf₂N] In order to depict the effect of carbon chain length on the structure, the space distribution functions were also computed and compared.

Xiaomin Liu;Yuling Zhao;Xiaochun Zhang;Guohui Zhou;锁江 张

Journal of Physical Chemistry B

2012-4-26

锁江 张;Hongyan He;Xiaoqian Yao

2011

Transport and thermodynamic properties of electrolyte solutions are very essential for development and design of lithium ion or lithium polymer batteries. An electrolyte database for lithium battery, which includes a quite number of organic solvents, lithium electrolytes and possible by-products (e.g. CO₂), has been compiled. Appropriate models have been evaluated for representing the variety of properties for solvents and electrolyte solutions, such as, conductivity, transference number, diffusivity, dissociation constant and so on. Particular attention has been given on conductivity in this paper, considering its essential importance for battery; several typical examples have been presented and discussed.

锁江 张;Akio Tsuboi;Hiroaki Nakata;Takeshi Ishikawa

Journal of Power Sources

2001-7

1-Ethyl-3-Methylimidazolium lactate ([EMIM][LAC]) is an environmental friendly ionic liquid with potential industrial applications. Attenuated total reflectance infrared spectroscopy (ATR-IR) and density functional theory (DFT) calculations were employed to investigate the molecular interactions between methanol and [EMIM][LAC]. The infrared spectra were analyzed by two methods: excess spectroscopy and two-dimensional (2D) correlation spectroscopy. In the ATR-FTIR spectra, v(C4,5-H), v(C2-H), v(alkyl), v(-OD), and v(-COO) all show blue shifts upon addition of methanol. 2D correlation analysis indicated that the v(imidazolium ring C-H) band varies before that of v(alkyl C-H) with increasing CD3OD content. The following sequential order of interaction strength is established by DFT calculations: EMIM-methanol -LAC>EMIM-LAC>LAC- methanol>EMIM-methanol. Journal compilation

Hongyan He;Hui Chen;Yanzhen Zheng;Xiaochun Zhang;Xiaoqian Yao;Zhiwu Yu;Suojiang Zhang

Australian Journal of Chemistry

2013

The FeCl₃-containing Lewis-acidic ionic liquids (ILs) [C₆mim]Cl/FeCl₃(1:1.5), [C₆mim]Cl/FeCl₃(1:2), [C₈mim]Cl/FeCl₃(1:1.5), and [C₈mim]Cl/FeCl₃(1:2) were used as extractants for desulfurization of model fuel and gasoline fuel, respectively. The results demonstrate that these ILs are effective for the removal of sulfur compounds from model fuel under different mass ratio of IL to model fuel (1:1, 1:3, 1:5, 1:10) at 25°C. The extractive performance of ILs increased as the molar ratio of FeCl₃ to [C_nmim]Cl(n = 6, 8) varied from 1:1 to 1:2. The selectivity of sulfur compounds by extraction process followed the order of dibenzothiophene (DBT)>benzothiophene (BT) > 4,6-dimethyldibenzothiophene (4,6-DMDBT). The sulfur removal of gasoline fuel containing sulfur content of 440.3 ppmw could be up to 85.8%; that is to say that the sulfur content of gasoline fuel varied from 440.3 ppmw to 62.4 ppmw after one extraction stage. Moreover, the [C₆mim]Cl/FeCl₃(1:2) can be recycled for at least 4 times with a little decrease in the desulfurization activity.

Hongshuai Gao;Shaojuan Zeng;Hongyan He;Haifeng Dong;Yi Nie;香平 张;锁江 张

Separation Science and Technology

2014-5

The addition of highly polar and aprotic cosolvents to ionic liquids has proven to considerably decrease the viscosity of the solution and improve mass transfer in many chemical reactions. In this work, the interactions between a representative pyridinium-based ionic liquid, N-butylpyridinium dicyanamide ([Bpy][DCA]), and a cosolvent, dimethylsulfoxide (DMSO), were studied in detail by the combined use of attenuated total reflection Fourier transform infrared spectroscopy, hydrogen nuclear magnetic resonance (¹H NMR), and density functional theory calculations. Several species in the [Bpy][DCA]-DMSO mixtures have been identified, that is, ion clusters can translate into ion pairs during the dilution process. DMSO formed hydrogen bonds (H bonds) simultaneously with [Bpy]⁺ cations and [DCA]^- anions but stronger hydrogen-bonding interactions with the [Bpy]⁺ cations than the [DCA]^- anions, and the intrinsic hydrogen-bond networks of IL were difficult to interrupt at low DMSO concentrations. Interestingly, hydrogen-bonding interactions reach the strongest when the molar fraction of DMSO is 0.4-0.5. Hydrogen-bonding interactions are prominent in the chemical shifts of hydrogen atoms in [Bpy]⁺ cations, and anisotropy is the main reason for the upfield shifts of DMSO in the presence of [Bpy][DCA]. The theoretical calculations offer in-depth studies of the structural evolution and NMR calculation.

Yaqin Zhang;Hongyan He;锁江 张;Maohong Fan

ACS Omega

2018

To investigate the effects of the substituents, substituent positions and axial chloride ligand on the geometric and electronic properties of the iron tetraphenylporphyrin (FeTPP), a series of the substituented iron tetraphenylporphyrins and their chlorides, FeT(o/p-R)PP and FeT(o/p-R)PPCl (R = -H, -Cl, -NO₂, -OH, -OCH₃), were systematically calculated without any symmetry constraint by using DFT method. For geometric structure, the substituent position and axial Cl ligand change the configuration of the iron porphyrin obviously. The orthosubstituents prefer making the phenyls perpendicular to the porphyrin ring; the axial chloride draws the central Fe ion ∼0.500 Å out of the porphyrin plane toward the ligand. With regard to electronic properties, it is found that ELUMO could be related to the catalytic activity. The electronwithdrawing group always lowers the energies of both frontier orbitals, while the electron-donating one heightens them simultaneously, but they affect the EHOMO and ELUMO in the same sequence, -NO₂ < -Cl < -H < -OH < -OCH₃. The substituent effects on the central Fe ion were explored by calculating NBO charge distribution, spin density and natural electron configuration.

Lu Wei;Yuanbin She;Yanmin Yu;Xiaoqian Yao;锁江 张

Journal of Molecular Modeling

2012-6

1-(2-Hydroxyl-ethyl)-imidazolium-based ionic liquids (HEIMX, X = Cl, Br, I), which have both acidic and basic characteristics, were covalently anchored onto a highly cross-linked polystyrene resin. The catalytic activity of these heterogeneous catalysts for the synthesis of cyclic carbonates via cycloaddition reaction of CO₂ with epoxides was studied. The effects of parameters, such as anions of the catalysts, reaction temperature, pressure, reaction time, and the amount of catalyst used, on the reaction were also investigated. It was demonstrated that the hydroxyl group in the catalyst had synergetic effect with the halide anion. As a result, high yield (80-99%) and excellent selectivity (92-99%) of cyclic carbonates could be achieved at mild conditions (2.5 MPa, 120 °C and 4 h) without any co-solvent. In addition, the catalyst recycle test showed that the supported catalyst could be reused for as many as six times without loss of catalytic activity.

Jian Sun;Weiguo Cheng;Wei Fan;Yaohong Wang;Zhenying Meng;锁江 张

Catalysis Today

2009-11-30

Polysulfides shuttle, although is not the only one, but definitely the most prominent problem which hinders the commercialization of lithium-sulfur cells. Herein, a functionally designed SiO₂ tethered 1-methyl-1-propylpiperidinium chloride (SiO₂-PPCl) ionic liquid nanoparticle is adopted as a bridgebuilder between the carbon carrier and lithium polysulfides (LPS) to modulate shuttle issues. The SiO₂-PPCl exerts effective adhesion to both polar LPS and nonpolar carbon carrier material by its special function groups, which make it act as a bridge between them, therefore, the dissolved LPS are prevented from migrating to lithium anode effectively, and the corresponding LPS shuttle is controllable by simply tuning the ratio of SiO₂-PPCl to sulfur. This strategy is demonstrated in a lithium sulfur suspension flow cell in which the shuttle effect is more serious because large quantity of electrolyte is adopted, and over 1000 cycles is achieved with high coulombic efficiency of 99%. Verified in a laboratory flow cell equipment, the approach of exploiting polysulfides bridgebuilder to control LPS shuttle manifests its feasibility and offers a new direction to develop lithium-sulfur batteries.

Song Xu;Yuanyuan Cheng;Lan Zhang;Kaihang Zhang;Feng Huo;Xiangping Zhang;锁江 张

Nano Energy

2018-9