Characterization of Camphene- and Fenchol-Based Hydrophobic Eutectic Solvents and Their Application in Aldehyde Extraction.

Binary terpenoid-based eutectic systems consisting of the natural substances camphene (CA), fenchol (FE), thymol (TH), menthol (ME), dodecanoic acid (DA), and 1-dodecanol (DO) are synthesized and screened for their Solid-Liquid Equilibrium (SLE) and eutectic compositions. Out of nine eutectic systems, 13 solvent compositions at eutectic points and next to them, in addition to the reference solvent, TH:ME, are synthesized and applied for the solvent extraction of the aromatic aldehydes vanillin (VAN), syringaldehyde (SYR), and -hydroxybenzaldehyde (HYD) from an acidic aqueous model solution. The extraction efficiency is determined from aldehyde concentrations measured by High-Performance Liquid Chromatography (HPLC), taking into consideration mutual solubility measured by Karl Fischer titration (KF) and a Total Organic Carbon-analysis (TOC).

Small magnesium clusters: between van der waals and valence bonds.

The magnesium molecules Mg(2), Mg(3), Mg(4), and Mg(5) have been isolated in rare-gas matrixes at 8 K and characterized for the first time by Raman spectroscopy. The vibrational frequencies were compared with those obtained by density functional theory calculations. The fundamental frequency of the dimer was observed at 97 cm(-1) (Ar matrix), and a bond length of d(Mg-Mg) = 340.