Journal of Ionic Liquids最新文献

5-Hydroxymethylfurfural (HMF) has emerged as a promising link between biomass and petrochemical products, offering great potential for application and promising market prospects. In this work, we investigated the catalyst for the synthesis of 5-hydroxymethylfurfural (HMF) from glucose using metal chloride or ionic liquid bearing Brönsted and Lewis acid using the continuous flow method. Under optimal conditions, a high HMF yield of 58 % was achieved at 120 °C within 20 min using IL 2/DMSO. For the study on metal chlorides, the reaction yield reached about 43 % HMF within 60 min using AlCl₃ (1 mmol) anhydrous. This research presents a remarkably effective method for synthesizing HMF.

The corrosion behavior of carbon steel in MEA-CO₂ media containing [BMIM]BF₄ was investigated in this work. The IL can effectively suppress the corrosion of the steel in the solution and facilitates the activation-passivation transition of the steel in the anodic polarization. Molecular dynamics simulations show that the cationic moiety of the ILs can strong adsorb on the surface of Fe in the parallel mode. However, the high content of the IL results in the slight reduction of the passive potential range of the steel, which may be related to the anions of the IL or the free F⁻ ions. It is demonstrated that the dissociation of BF₄⁻ ions gives rise to a relatively high concentration of F⁻ ions in the solution containing [BMIM]BF₄. The addition of NaF indicates the free F⁻ ions can induce the similar localized corrosion of the steel to that in the case of [BMIM]BF₄.

The indiscriminate application of diverse broad-spectrum antimicrobials has escalated nosocomial infections into a critical global public health quandary. Currently, traditional antibiotics' efficacy against these infections becomes limited, necessitating a concerted pursuit of more efficacious antimicrobial agents. It is noteworthy that taurine (tau) and cepharanthine (cep) are both biologically active compounds, with taurine constituting a vital nutrient to human health and cepharanthine exhibiting certain antibacterial attributes. However, while cepharanthine displays intrinsic antibacterial features, its monomeric utility is constrained. This study thus investigated the formulation process of merging taurine with cepharanthine, and rigorously assessed the antimicrobial potential of the taurine-cepharanthine complex (denoted as [cep][tau]). The outcomes indicated that this complex, [cep][tau], exhibited antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae, which was on par with the efficacy of cepharanthine on its own. This observation implies that taurine did not antagonize the antibacterial potency of cepharanthine, offering novel avenues for the development of innovative pharmaceuticals targeting hospital-acquired infections.

The binding interactions in complex formation between surface active ionic liquids (SAILs) and polymers (nonionic or anionic) are gaining attention because of their potential applications in novel materials. Therefore, the use of a variety of measurements is required for a better understanding of the interactions involved in polymer/SAIL formation. Here, we have investigated the interactions of nonionic poly(vinylpyrrolidone) (PVP) and anionic sodium carboxymethylcellulose (NaCMC) polymers with SAIL 1-tetradecyl-3-methylimidazolium chloride [C₁₄mim][Cl] in aqueous solution using different measurements such as conductivity, surface tension, fluorescence spectroscopy, dynamic light scattering (DLS) and rheometric measurements. The surface tension, conductivity and fluorescence profiles for SAIL-NaCMC systems provide distinct breakpoints that correspond to four different aggregation states: the concentration at which SAIL monomers begin to attach to the polymer chain (C₁), the critical aggregation concentration C₂ (cac), the saturation concentration (C_S) and the critical micelle concentration (cmc). In the case of SAIL-PVP systems, the surface tension and fluorescence profiles confer three transition states: C₂ (cac), C_S and cmc and only two transition states have been observed in conductivity curves. The cooperative binding of SAIL to the NaCMC/PVP chain at the solution interface was analyzed by calculating various thermodynamic and interfacial parameters. Strong complexation was observed between NaCMC-SAIL molecules compared to PVP-SAIL systems at the air-solution surface. This is due to the non-ionic character of the PVP chain, which shows weak interactions with SAIL in comparison to NaCMC. Furthermore, DLS and fluorescence measurements were used to investigate the interactions between SAIL and polymers.

We have synthesized imidazopyridine-type ionic liquids and evaluated their properties. [C_nimpy][Br] (n = 4, 6, 8, 10), in which an alkyl group was introduced at the N₁ position of imidazo[1,2-a]pyridine, were all solid at room temperature. Exchange of the counteranions of [C_nimpy][Br] with N(CN)₂⁻ and FSI⁻ gave the ionic liquids [C_nimpy][N(CN)₂] and [C_nimpy][FSI] in the liquid state at room temperature. In particular, the DSC thermogram of [C₁₀impy][FSI] showed a clear melting point at 22 °C. In [C_nimpy][TFSI], ionic liquids consisting of cations with short alkyl chain lengths (n = 4,6) were solids at room temperature, while those with long alkyl chain lengths (n = 8,10) were liquids. [C_nimpy][FSI] has lower viscosity than other anion-consisting ionic liquids which showed a liquid state at room temperature. [C_nimpy][FSI] has lower viscosity than other anion-containing ionic liquids. In particular, [C₄impy][FSI], with its relatively short alkyl chain length, exhibited a viscosity of 101 mPa·s at 25 °C, which renders it suitable for practical applications. [C₄impy] [FSI] (50 μM acetonitrile solution) showed fluorescence with maximum absorption at 336 nm. Its fluorescence wavelength was shorter than that of imidazo[1,2-a]pyridine, whereas its fluorescence quantum yield (Φ_F 0.39) was higher. Therefore, it is expected to be used as a composite material by employing FRET with a substance that exhibits fluorescence in the visible region.

CO₂ capture from industrial processes and power plants, contribute to curbing global warming and advancing sustainability efforts. This study involves the design and synthesis of novel mesoporous silica supported ionic liquid based adsorbents for carbon dioxide capture. Utilization of MSILs delves into the efficiency and mechanisms of CO₂ adsorption, offering insights for sustainable carbon capture technologies in combating greenhouse gas emissions. 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium ethyl sulfate and 1-ethyl-3-methylimidazolium methylsulfate ionic liquids were anchored on the surface of mesoporous silica which then led to highly efficient adsorbent material. Simple, efficient and cost saving methodology was performed to synthesize such highly efficient CO₂ adsorbent materials. In addition, we theoretically predicted the favorable interaction mechanism of chosen molecular entities for CO₂ adsorption using density functional theory (DFT) analysis. Theoretical results depict the strong interaction of molecular entities with CO₂ gas molecules which is clearly evident from the experimental findings.