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Deep eutectic solvents (DESs) are recent solvents that have the basic characteristics close to ionic liquids, and they have been applied in several reactions. Adding molecular solvents especially w...

Deep eutectic solvents (DESs) are a new class of ionic liquids which have been applied in many chemical reactions therefore, the investigation of their physicochemical properties such as hydrogen bond property and ion delocalization, are important. We measured solvatochromic parameters of three different DESs, namely urea-choline chloride (reline), ethylene glycol-choline chloride (ethaline), and glycerol-choline chloride (glyceline) and their binary mixtures with different mole fractions of poly ethylene glycol (PEG 400) as co-solvent. Solvatochromic results showed that the reline has the biggest polarity in these three DESs, but the lowest in hydrogen bond donor and acceptor abilities. In binary mixtures of DESs with PEG 400, π* and α values are decreasing with increasing the mole fraction of PEG 400 which is in good agreement with these parameters in mixed solvents. Molecular dynamic simulations confirmed that there are hydrogen bonds between urea, ethylene glycol, glycerol and choline chloride in pure DESs, and their amount calculated in all DESs and also with some mole fractions of PEG 400. Moreover, delocalization of chloride in DESs, were calculated for all compositions by MD simulations analysis. Also, MD simulations confirmed result of the experimental finding and preferential solvation model.

Experimental and computational investigations have been conducted in this study to assess the influence of municipal waste pyrolyzed biochar impregnated clay composites on antibiotic removal as a material for wastewater treatment and simultaneous value-addition for waste. The surface potential (zeta potential) of the pristine biochar and composite samples are found to be within the range ~10 to ~ −40 mV in the pH range 2–10. The presence of different inorganic salt solutions influences the electrophoretic mobility of the dispersed phase in a suspension, as well as its zeta potential. In addition of Na+ salt solutions, the Na+ ions undergo electrostatic interaction with the negatively charged biochar samples and form a double layer at the interface of biochar and ionic salt solution. Molecular dynamics simulations have been employed to understand experimental findings, ions adsorption and solute-solvent interactions at the molecular level of two biochar B7 (seven benzene rings, one methoxy, one aldehyde and two hydroxyls groups) and B17 (seventeen benzene rings, one methoxy, two hydroxyls and two carboxylic acid groups) in salts aqueous solutions. The results confirm that hydroxyls and carboxylate groups of biochar are responsible for solute-solvent interactions. Successful removal of tetracycline antibiotics is observed with 26 mg/g maximum adsorption capacity with montmorillonite biochar composite. This study confirms that interactions between amide and hydroxyl groups of tetracycline with hydroxyl and carboxylate groups of biochar play the key role in the adsorption process. The solution pH and presence of different background electrolytes effectively influence the process of solute-solvent interactions as well as adsorption efficacy towards tetracycline adsorption.

Fluorination of graphene nanomaterials has multitude merits owing to the peculiar temperament of the carbon-fluorine (C-F) bond. However, the current synthesis modalities of fluorinated graphene (FG) are based on the usage of toxic materials at high temperatures, which are problematic to be used. The methods to overcome these problems are challenging for chemists. Ionic liquids (ILs) have been used in several chemical processes as auxiliaries and eco-friendly alternatives instead of volatile organic solvents because of their properties. Consequently, herein we exploited a highly effective and green process for the synthesis of FG at mild temperature (80 °C) by using ammonium fluoride salt as fluorine agent and a synthesized acidic IL ([TEA]+[TFA]–) as a solvent. Our goal was to synthesize enriched FG with a high degree of fluorination (66.4 wt.% of F) and F/C ratio (2.2), which measured and confirmed by XPS analysis. Subsequently, the obtained FG was used as a nanocarrier for delivery of curcumin to cancerous cells. The in-vitro results showed that these nanosheets possessed a higher Cur-loading efficiency (78.43%) than commercial FG (52.12%) due to the sheet-like structure with folded edges. This, in turn, translated into an excellent in-vitro anti-cancer effect when tested against cancerous cells.

Novel protic ionic liquids (PILs) and low melting mixtures (LMMs) have been synthesized based on green components, cheap sources, the high purity, and easy way of preparation. PILs include [Im][For], [Im][Ace], [Im][Pro], [Im][But], and [Im][Pen]. LMMs include [ImCl][EG], [ImCl][Gly], [ImCl][PEG], [ImCl][ETA], and [ImCl][carbohydrate] + DMSO. These solvents contain imidazolium/imidazolium chloride as a cation/salt. NMR spectroscopy was used to analyze the structures of solvents. Melting points, and thermal stabilities were measured via thermal analyses. We were looking to synthesize new DESs with imidazolium chloride (ImCl); Due to lack of observation the melting points for mixtures of ImCl + hydrogen bond donors (HBDs), these mixtures were called low melting mixtures (LMMs) in this work. The mixtures of PILs/LMMs with molecular solvents showed good implications for homogenous and heterogenous systems which can be used for separation goals. Solubilities of carbohydrates, and some amino acids were tested in pure and mixed of ILs with molecular liquids. Adding DMSO to ILs/LMMs increased the dissolution of carbohydrates. As well, adding water to ILs had a remarkable effect for increasing the solubility of amino acids.

The spectrophotometrical behavior of pyridinium N-phenolate betaine dye used as a solvatochromic indicator of solvent polarity is studied in binary mixtures of tetra-n-butylammonium glycinate and tetra-n-butylammonium l -alaninate with molecular solvents such as acetonitrile, ethyl acetate, and 1-butanol. This study shows that the solvent/solvent interactions, which cause preferential solvation of the dye solute, should not be established for studied amino acid-based ionic liquids with conventional molecular solvent mixtures. After addition of mole fraction of the ionic liquid, the intramolecular charge-transfer absorption spectrum of the betaine dye shows a dual peak structure. Variation of UV–Vis spectra demonstrates the existence of a relationship with the type of the molecular solvent. Molecular dynamic simulations showed clearly different compositions in the solvation shells of betaine dye.