Recovery of Titanium from Ilmenite HCl Leachate Using a Hydrophobic Deep Eutectic Solvent

Abstract

Currently, it is difficult to obtain high-purity titanium from ilmenite to produce titanium dioxide (TiO2). More severely, it causes serious environmental pollution. In this paper, a new hydrophobic deep eutectic solvent (HDES), a combination of decanol (DEO) as a hydrogen bond donor (HBD) with N,N-diisooctylacetamide (DOA) as a hydrogen bond acceptor (HBA), for the environmentally friendly recovery of Ti­(IV) from ilmenite HCl leachate is proposed. The prepared HDES had low water cross-contamination, low viscosity, and sufficient density difference of HDES–water. The formation mechanism of HDES had been thoroughly revealed. In the ilmenite HCl leachate, the extraction effect of HDES on all metal ions had been studied in detail. Finally, rutile TiO2 and Fe2O3 were successfully synthesized using the obtained solutions as raw materials. The extraction mechanism characterized by Fourier transform infrared and 1H NMR spectroscopy was consistent with that determined by density functional theory (DFT) calculations. The slope method was used to study the effects of HBD, HBA, H+, Cl–, and H2O on the extraction of metal ions by HDES. In addition, the complex structures of HDES formed in the HCl solution are given. This article may thus help improve the sustainable utilization of some related metal ions from the real ore.

Green synthesis of highly stable CsPbBr3 perovskite nanocrystals using natural deep eutectic solvents as solvents and surface ligands

“…S1 and S2,† the formation of Thy : LacA and Thy : DecA can also be proved by FT-IR and 1 H NMR. 39,40…”

An Overview of Structure and Dynamics Associated with Hydrophobic Deep Eutectic Solvents and Their Applications in Extraction Processes

“…[43] This HDES exhibited low viscosity and provided a green path for the extraction process without contaminating the water phase. [43] Marrucho and co-workers used different combinations of HBDs and HBAs fatty acids to prepare HDESs with low viscosity to remove bisphenol A from water by exercising the advantage of hydrophobicity present in the HDESs. [41] Tuinier and co-workers defined four criteria for an HDES to be used as sustainable designer solvents for extraction processes.…”

“…The HDESs thus obtained were used to extract micropollutants like nitenpyram, acetamiprid, thiamethoxam, and imidacloprid from an aqueous environment [40] . Ren and co‐workers prepared a HDES based on decanol and N,N‐diisooctylacetamide and utilized it for extracting titanium from ilmenite HCl leachate [43] . This HDES exhibited low viscosity and provided a green path for the extraction process without contaminating the water phase [43] .…”

“…Ren and co‐workers prepared a HDES based on decanol and N,N‐diisooctylacetamide and utilized it for extracting titanium from ilmenite HCl leachate [43] . This HDES exhibited low viscosity and provided a green path for the extraction process without contaminating the water phase [43] . Marrucho and co‐workers used different combinations of HBDs and HBAs fatty acids to prepare HDESs with low viscosity to remove bisphenol A from water by exercising the advantage of hydrophobicity present in the HDESs [41] .…”

Tailored ternary hydrophobic deep eutectic solvents for synergistic separation of yttrium from heavy rare earth elements

“…48,60,61 Compared with traditional molecular solvents and ILs, HDESs as a new generation of green solvents have a number of important advantages such as easier preparation processes, no need for purification, low cost, potential biodegradability and negligible toxicity, which highly adhere to the 12 principles of green chemistry. 52,56,62 The unique combination of physical and chemical properties of HDESs facilitates diverse applications in green chemistry, 63 such as the extraction of pharmaceuticals, 61 heavy metals recovery from wastewater, 64 the separation of carboxylic acids, 65 the selective extraction of boric acid, 66,67 liquid-liquid extraction and the separation of metal resources, [68][69][70][71][72] etc.…”