Green and efficient coordination of Ti(IV) with bisamide solvent

Abstract

Titanium(Ti) is known as a strategic metal due to its excellent physical and chemical properties. Ti based materials are widely used in many fields, such as aerospace, biomedical, and photovoltaic materials. Since the metal smelting industry is often accompanied by high pollution, deep eutectic solvent, as a new type of environmentally friendly solvent, is gradually being widely used in the field of metal separation and purification. Through the transformation from non-ionic organic deep eutectic solvents (DESs-5) to inorganic deep eutectic solvents (DESs-M), the efficient coordination of Ti(IV) in acidic chloride medium was achieved. Under the optimal condition, over 95% of Ti(IV) in aqueous solution can be coordinated into DESs in a single stage, which can be used for the separation and purification of Ti(IV). The formation mechanism of DESs-5 was revealed by the quantum chemistry method and the lowest energy mechanism in the conversion reaction process was revealed by frontier molecular orbital (FMO) theory. The thermodynamic and kinetic processes of the conversion reaction were analyzed, which provided important research data for the construction of DESs-based Ti(IV) separation and purification system.