scholarly journals Dissolution of Chitin in Deep Eutectic Solvents Composed of Imidazolium Ionic Liquids and Thiourea

2019 ◽  
Vol 3 (4) ◽  
pp. 90 ◽  
Author(s):  
Satoshi Idenoue ◽  
Kazuya Yamamoto ◽  
Jun-ichi Kadokawa

Chitin is an abundant organic resource but shows poor solubility, leading to difficulty in utilization as materials. We have already reported that an ionic liquid (IL), 1-allyl-3-methylimidazolium bromide, dissolves chitin at concentrations up to ca. 5 wt %. However, the color of the resulting solution is blackened, mainly owing to the presence of bromide. On the other hand, some deep eutectic solvents (DESs) have been already reported to dissolve chitin. In this study, we found that DESs composed of imidazolium ILs and thiourea dissolved chitin without obvious coloring. DESs are systems formed from eutectic mixtures of hydrogen bond accepters and donors. We first prepared DESs by heating mixtures of imidazolium ILs with thiourea at 100 °C for 30 min with stirring. Predetermined amounts of chitin were then added to the DESs, and for the dissolution, the mixtures were left standing at room temperature for 24 h, followed by heating at 100 °C for 24 h with stirring. The dissolution processes were evaluated by CCD camera views, which revealed in most cases the dissolution of chitin at 2–5 wt % concentrations with the present DESs.

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6344
Author(s):  
Philipp S. Borchers ◽  
Patrick Gerlach ◽  
Yihan Liu ◽  
Martin D. Hager ◽  
Andrea Balducci ◽  
...  

In this work, two new redox-active ionic liquids, one based on 2,2,6,6-tetramethylpiperidine-N-oxide and the other based on 4,4′-bipyridine, are synthesized and characterized. A ferrocene-based redox-active ionic liquid is used for referencing the results. All ionic liquids are formed via salt-metathesis from halogenate to bis(trifluoromethylsulfonyl)imide. Their fundamental thermal characteristics are assessed with differential scanning calorimetry. While the imidazolium ionic liquids show no melting point, the phase transition is well observable for the viologen-based ionic liquid. The properties of the neat redox-active ionic liquids and of binary mixtures containing these ionic liquids (0.1 m) and 1-butyl-1-methyl pyrrolidinium-bis(trifluoromethylsulfonyl)imide have been investigated. Finally, the use of these binary mixtures in combination with activated carbon-based electrodes has been considered in view of the use of these redox-active electrolytes in supercapacitors.


Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 642 ◽  
Author(s):  
Mayur Thul ◽  
Yao-Peng Wu ◽  
Yi-Jyun Lin ◽  
Shu-Lin Du ◽  
Hsin-Ru Wu ◽  
...  

Tunable aryl imidazolium ionic liquids acting as Brønsted acid ionic liquids were found to be efficient catalysts for per-O-acetylation and reductive ring opening of benzylidene acetals. This method requires a truly catalytic amount of the least expensive available ionic liquids that are water-stable and reusable and also stable at room temperature. The reactions were obtained in one hour with good to excellent yields. These reactions can form C−O and C−H bonds with a high atom economy. Furthermore, the ionic liquid is an anomeric selective catalyst in per-O-acetylation and reductive ring opening of benzylidene acetals of sugar moieties.


RSC Advances ◽  
2021 ◽  
Vol 11 (20) ◽  
pp. 12398-12422
Author(s):  
Amir Sada Khan ◽  
Taleb H. Ibrahim ◽  
Nabil Abdel Jabbar ◽  
Mustafa I. Khamis ◽  
Paul Nancarrow ◽  
...  

Extraction of phenol from aqueous phase to ionic liquid phase.


2015 ◽  
Vol 10 (2) ◽  
pp. 135-145 ◽  
Author(s):  
Prasanta Kumar Mohapatra

Abstract This review article gives a comprehensive account of the extraction of actinide ions using room temperature ionic liquid-based solvent systems containing diglycolamide (DGA) or functionalized DGA extractants. These extractants include multiple DGA-functionalized ligands such as tripodal DGA (T-DGA) and DGA-functionalized calix [4]arenes (C4DGA). Apart from metal ion extraction behaviour, other important features of the ionic liquid-based solvent systems such as separation behaviour, luminescence spectroscopic results, thermodynamics of extraction and radiolytic stability of the ionic liquid-based solvents are also reviewed. Results from studies on DGA-functionalized task-specific ionic liquids (TSIL) are also included in this review article.


2018 ◽  
Vol 20 (20) ◽  
pp. 14234-14241 ◽  
Author(s):  
Helena Passos ◽  
Teresa B. V. Dinis ◽  
Ana Filipa M. Cláudio ◽  
Mara G. Freire ◽  
João A. P. Coutinho

A predictive model for ionic liquid/salt aqueous biphasic systems’ formation based on the hydrogen bond basicity of ionic liquids and molar entropy of hydration of salts.


2021 ◽  
Author(s):  
Phatsawit Wuamprakhon ◽  
Ruttiyakorn Donthongkwa ◽  
Kanit Hantanasirisakul ◽  
Vinich Promarak ◽  
Jumras Limtrakul ◽  
...  

The specific cell capacitance, equivalent series resistance (ESR) and equivalent distributed resistance (EDR) of porous carbon-based supercapacitors linearly depend on the cation molecular length (1 dimension) of room-temperature ionic liquids.


2019 ◽  
Vol 25 (3) ◽  
pp. 276-280
Author(s):  
Canan URAZ

In this study, electroless nickel (EN) plating on acrylonitrile butadiene styrene (ABS) engineering plastic using room temperature ionic liquids (RTIL) was studied. Electroless plating is a fundamental step in metal plating on plastic. This step makes the plastic conductive and makes it possible to a homogeneous and hard plating without using any hazardous and unfriendly chemical such as palladium, tin, etc. In the industry there are many distinct chemical materials both catalysts and activation solutions for the electroless bath which is one of the most important parts of the process. In this study the effects of the ionic liquid, plating time, and sand paper size were investigated on electroless nickel plating. The etching and the plating processes were performed with environmentally friendly chemicals instead of the chromic and sulphuric acids used in the traditional processes. Experiments were carried out with and without ionic liquid, EMIC, 1-ethyl-3-methyl imidazolium chloride (C6H11N2Cl), and with 400, 500 and 800 grit sandpaper with the application of the sand attrition process and 70, 80, and 90 °C bath temperatures with 30, 60, and 90 minutes of deposition time. The surface morphology and the thickness of deposit analysis were performed using the Fischer scope X-Ray XDL-B System, X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). Due to the results of the experiments and analysis, the electroless nickel plating on ABS plastic was a success. The best plating was obtained at 5.010 μm as the maximum plating thickness, at 90 min of plating time and 80 °C as the plating bath temperature for electroless nickel plating on ABS plastic whit the surface activated with 800 grit sandpaper using EMIC ionic liquid. DOI: http://dx.doi.org/10.5755/j01.ms.25.3.20116


Author(s):  
Barbara J. Kinzig ◽  
Paul Sutor ◽  
Gregory W. Sawyer ◽  
Alison Rennie ◽  
Pamela Dickrell ◽  
...  

Room temperature ionic liquids (RTILs) are molten salts with melting points at or below room temperature. RTILs have recently been recognized as novel lubricants. Only a few have previously been evaluated.


Lubricants ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 37 ◽  
Author(s):  
Ignacio Garcia ◽  
Silvia Guerra ◽  
Juan de Damborenea ◽  
Ana Conde

Deep eutectic ionic liquids (DES) possess similar properties to conventional ionic liquids (ILs). However, ILs cannot be considered as environmentally friendly compounds due to both its processing and synthesis, which could have significant polluting effects. On the contrary, deep eutectic solvents (DESs) can be biodegradable, non-toxic, and have a lower price than most ILs, making them potentially useful in a wide variety of advanced technological applications, such as tribology. On the other hand, graphene has recently been proposed as an extremely promising lubricant due to its combination of mechanical properties and chemical stability as well as its “green” character. In the present paper, graphene flakes (≈250 nm) have been used as an additive to DES composed of choline chloride (ChCl)-urea, ChCl-ethylene glycol, and ChCl-malic acid. According to the results, the addition of 1 wt% graphene reduces friction coefficient (COF) and, notably, prevents adhesive wear, reducing wear rate on steel-steel sliding contacts.


RSC Advances ◽  
2019 ◽  
Vol 9 (20) ◽  
pp. 11322-11330 ◽  
Author(s):  
Guanzhou Zhu ◽  
Michael Angell ◽  
Chun-Jern Pan ◽  
Meng-Chang Lin ◽  
Hui Chen ◽  
...  

Room temperature ionic liquids (RTILs) are solvent-free liquids comprised of densely packed cations and anions. Properties of Py13Cl–AlCl3 ILs were studied and compared with EMIC-AlCl3 ILs for use as electrolyte in Al–graphite battery.


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