Effects of thiol substitution in deep-eutectic solvents (DESs) as solvents for metal oxides

This study deals with an investigation of how substitution of an alcohol group by a thiol group in mixtures of choline chloride with a series of bio-sourceable molecules affects the physico-chemical properties of the mixtures and their ability to dissolve metal oxides. All of the thiol mixtures studied showed a higher affinity and selectivity for late transition metals and the physical properties of the mixtures were improved compared to their alcohol analogues (i.e. lower viscosity, wider liquid range). The metal solubility was assessed via determination of the final concentration of the metal oxides dissolved in thiol mixtures via inductively coupled plasma optical emission spectroscopy (ICP-OES). The thiol function selectively improved the solubilities of the late transition metal oxides (i.e. copper and zinc), which are valuable metals often present as residue in industrial waste. The solubility of iron oxides was much lower than that of the valuable metals, which is a significant benefit in industrial applications. The different solubilization behaviour of metal oxides in the thiol and alcohol mixtures was further investigated via UV-vis absorption and infrared spectroscopy. This study allowed the potential of these deep-eutectic solvents for the selective recovery of metals to be assessed

Synthesis of extractants and ionic liquids from renewable chemicals

A library of new extractants and ionic liquids derived from Guerbet alcohols. An optimised protocol for the synthesis of Guerbet alcohols. Solvent-extraction processes for the separation of metals ions, based on extractants and ionic liquids derived from Guerbet alcoholsstatus: publishe

Synthesis of Guerbet ionic liquids and extractants as ß-branched biosourceable hydrophobes

This study investigates the synthesis of β-branched amines and β-branched quaternary ammonium chloride ionic liquids as novel extractants. The synthesis methodology was tailored to facilitate the reaction scale-up and the use of biorenewable starting materials. The developed process is an overall green, easy and straightforward synthesis of β-branched amines, and ammonium salts, starting from linear aldehydes. In order to evaluate the potential of the synthesised materials in applications, the rheology, density, thermal stability, chemical stability, phase transitions, mutual solubility with water of the novel extractants was studied.status: Published onlin

One-pot synthesis of symmetric imidazolium ionic liquids N,N-disubstituted with long alkyl chains

status: publishe

Evaluation of 11 ionic liquids as potential extraction solvents for benzodiazepines from whole blood using liquid-liquid microextraction combined with LC-MS/MS

Ionic liquids (ILs) are becoming a trending topic in sample preparation technology, due to their low volatility, low flammability and tunable physiochemical properties. The latter affords the opportunity for creating task-specific solvents. In toxicology, these tailored ILs were not introduced yet; however, they can be significant for drug extraction purposes. This study screens 11 commercially available ILs as potential extraction media for benzodiazepines from blood samples via liquid-liquid microextraction, coupled to liquid chromatography - tandem mass spectrometry (LC-MS/MS). Structure-extraction relationships were deducted from recovery and matrix effect results (n = 5), allowing us to devise some of the favorable features in a tailored IL for benzodiazepine extraction. Overall, long alkyl chains are to be avoided, as they may sterically hinder desirable π-stacking interactions. For the same reason, aromatic planar cations, as imidazolium and pyridinium, were more effective in comparison with ammonium and pyrrolidinium. Furthermore, viscosity negatively impacted both recoveries and matrix effects. High viscosities limited mass transfer during dispersion and impeded electrospray ionization processes. In conclusion, this study evaluates which physicochemical features an IL should possess to efficiently extract benzodiazepines from whole blood.status: accepte

Effects of thiol substitution in deep-eutectic solvents (DESs) as solvents for metal oxides

status: publishe