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Abstract: Quantum chemical calculations of the structures and cation-anion interaction of 1-ethyl-3-methylimidazolium lactate ([Em-im][ 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.

Abstract: 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 remarkably enhanced in some imidazolium chloride by the addition of urea, and the solubility of ZnO in 1:1 [Amim]Cl/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]Cl/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.

Abstract: 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.

The technologies of ionic-liquid-mediated extraction have shown the good prospects for replacing traditional methods for separating natural bioactive homologues. However, so far, the roles and interactions of the anions and cations in the extraction process are not clear, which seriously hinders the further exploration of this new extraction technology. In this work, we report a detailed computational study, combined with experiment, on the interactions and hydrogen bonds between 1-butyl-3-methylimidazlium hexafluorophosphate ([Bmim][PF6]) ionic liquid (IL) and natural bioactive homologues, namely, three soybean isoflavone aglycones as model compounds. The distribution coefficients, D, of the three aglycones were experimentally determined in the [Bmim][PF6]–water biphasic system, and the order was found to be genistein (182.6) > daidzein (51.4) > glycitein (41.9). In DFT calculations, the lowest-energy complexes were obtained, and it was found that H-bonds are explicit intermolecular interactions in these complexes and that the IL can recognize these similar homologues by forming different H-bonds with the phenolic hydroxyls of aglycones. Furthermore, we found that the anions play a more important role in recognition than the cations. Subsequently, results of molecular dynamics (MD) simulations exhibited a good match with the structures of the isolated complexes calculated by DFT and also discovered that H-bonds were the main interactions between the anions and the phenolic hydroxyls in the first solvation shell.

A fluidized bed process for the one-step synthesis of methyl acrylate (MA) using methyl acetate (Ma) and formaldehyde (FA) was developed for the first time. New spherical antiwear acid–base catalysts Cs–P/γ-Al2O3were prepared using ultrasonic impregnation method and characterized with XRD, BET, SEM, PSD, ICP, TG/DTA, NH3-TPD, and CO2-TPD methods. Catalytic performance was evaluated, and 10.0 wt % Cs–5.0 wt % P/γ-Al2O3with weak acid–base sites was determined to be the best catalyst for MA production. Response surface methodology (RSM) was employed to optimize aldol condensation of Ma with FA over 10.0 wt % Cs–5.0 wt % P/γ-Al2O3. The effects of various process parameters such as reaction temperature, molar ratio of Ma and FA, and liquid hourly space velocity (LHSV) on MA yield were addressed by Box–Behnken experimental design (BBD). The coefficient of determination (R2) of this model was 0.997, and 39.5 mol % yield of MA was obtained after optimization. The developed catalyst exhibited high stability, with no significant decrease in catalytic activity after 1000 h of lifetime evaluation.

With 3D framework structure and special corner-sharing characteristics, natrium superionic conductors (NASICONs) can vary their crystal structure with temperature change or on cation insertion/desertion, serve as both electrode and electrolyte materials, which make them fascinating in energy storage applications. However, those structure characteristics also bring about challenges on the understandings of charge transport mechanism, such as the precise cation/electron diffusion passage and the means to enhance or adjust it. Herein this review, we take typical NASICONs, the single ion conductor, Na3Zr2Si2PO12(NZSP) and ion/electron mixed conductor, Na3V2(PO4)3(NVP) as the examples, and briefly review the studies on charge transport mechanism as well as the strategy to enhance it. We find that doping is the mostly viable method to increase both ionic and electronic conductivity, while, considering the different roles that NASICON may act in energy storage, special attention should be paid on the doping effect. Typical doping elements were classified by their functions, such as working on the SE bulk, grain boundary, or enrich the vacancies. We found that some elements could enhance both σiof NZSP and σeof NVP, while most of the σeresults were obtained on pallet level, therefore, advanced particle-level electronic conductivity testing method or instrument is required.

A novel dual amino-functionalized ionic liquid, 1, 3-di (2′-aminoethyl)-2-methylimidazolium bromide (DAIL), was synthesized and investigated as a potential absorbent for CO2capture. CO2absorption behavior on pressure, temperature and concentrations of DAIL in aqueous solution were studied, and the absorption mechanism was investigated by spectroscopic methods and DFT calculations. The CO2capture capacity of 18.5 wt % and good thermal stability (Td= 521.6 K) make DAIL a good candidate for industrial applications for CO2capture.

Crystalline phase is the key factor for catalyst activity. The zirconium modified PCs/γ-Al2O3samples were prepared through a simple step incipient-wetness impregnation method. The raw materials and samples were characterized by thermogravimetric-differential analysis (TG-DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), temperature-programmed desorption of ammonia and carbon dioxide (NH3- and CO2-TPD). The effects of calcination temperature and zirconium content on structure, chemical transformation, and acidity-basicity were investigated. Calcination temperature exhibited the major effect on the crystalline phase of samples. The new phase of Al0.1Zr0.9O1.95was exhibited which was above 650°C. In addition, zirconium content was influenced by the acidic and basic properties of the surface. The acidity and basicity of the ZrPCs/γ-Al2O3sample increased with the increasing of zirconium content.