Separation of Rare-Earth Ions from Mine Wastewater Using B12S Nanoflakes as a Capacitive Deionization Electrode Material

In this study, nanoflakes of B12S were fabricated by plasma-assisted reaction of sulfur dichloride in an ionic liquid at room temperature using europium boride as a hard template. The nanoflakes had an average width and thickness of about 3 1urn and 9.6 nm, respectively, and a large specific surface area of 1197.2 m2 g 1. They behaved like typical electric double-layer capacitors with a capacitance of 201.2 F g 1 at 0.2 mA cm 2 During capacitive deionization to recover rare-earth ions, the nanoflakes had higher adsorption selectivity for Sm3+ than for other competing ions present in real mine waste water. This is due to the strong interaction of the electron-concentered S-groups (S’’’) of the nanoflakes with S m3+. This provides an alternative to construct efficient systems to specifically remove Sm3+ from aqueous solution using B12S nanoflakes. This process demonstrates that other boron sulfide compounds can be used to recover valuable ions by capacitive deionization.

A Regioselective Synthesis of Novel Functionalized Organochalcogen Compounds by Chalcogenocyclofunctionalization Reactions Based on Chalcogen Halides and Natural Products

The regioselective synthesis of novel functionalized condensed organochalcogen compounds by chalcogenocyclofunctionalization reactions based on chalcogen halides and the natural products thymol and carvacrol has been developed. The reactions of selenium dibromide with allyl thymol and allyl carvacrol proceeded in methylene chloride at room temperature in the presence of NaHCO3 affording bis[(7-isopropyl-4-methyl-2,3-dihydro-1-benzofuran-2-yl)methyl] and bis[(4-isopropyl-7-methyl-2,3-dihydro-1-benzofuran-2-yl)methyl] selenides in 90–92% yield. Similar sulfides were obtained in 70–72% yields by the reaction of sulfur dichloride in chloroform under reflux. Trihalotellanes containing the same organic moieties were synthesized from allyl thymol, allyl carvacrol and tellurium tetrachloride or tetrabromide in quantitative yields. Corresponding functionalized ditellurides were prepared in 91–92% yields by the reduction of the trichlorotellanes with sodium metabisulfite in two-phase solvent system. The comparison of reactivity of sulfur, selenium and tellurium halides in chalcogenocyclofunctionalization and distinguishing features of each reaction were discussed.

Novel and Simple Synthesis of Brominated 1,10-Phenanthrolines

A novel, simple, and reasonably efficient synthesis of 3,8-dibromo-1,10-phenanthroline, 3,6-dibromo-1,10-phenanthroline, 3,5,8-tribromo-1,10-phenanthroline, and 3,5,6,8-tetrabromo-1,10-phenanthroline is presented herein. The crucial role of a new catalyst (sulfur dichloride – SCl2) for the bromination of 1,10-phenanthroline is reported. The bromination of 1,10-phenanthroline monohydrate in the presence of SCl2 and pyridine yielded the brominated compounds, previously only possible through the complicated multi-step and tedious Skraup synthesis method. The application of the bromination catalyst SCl2 as a medium-strength Lewis acid is demonstrated for the first time, and the results are compared with the behaviours of known weak (sulfur chloride – S2Cl2) and strong (thionyl chloride – SOCl2) bromination catalysts. A reaction mechanism was proposed.