Application of Ionic Liquids for the Recycling and Recovery of Technologically Critical and Valuable Metals

Abstract

Population growth has led to an increased demand for raw minerals and energy resources; however, their supply cannot easily be provided in the same proportions. Modern technologies contain materials that are becoming more finely intermixed because of the broadening palette of elements used, and this outcome creates certain limitations for recycling. The recovery and separation of individual elements, critical materials and valuable metals from complex systems requires complex energy-consuming solutions with many hazardous chemicals used. Significant pressure is brought to bear on the improvement of separation and recycling approaches by the need to balance sustainability, efficiency, and environmental impacts. Due to the increase in environmental consciousness in chemical research and industry, the challenge for a sustainable environment calls for clean procedures that avoid the use of harmful organic solvents. Ionic liquids, also known as molten salts and future solvents, are endowed with unique features that have already had a promising impact on cutting-edge science and technologies. This review aims to address the current challenges associated with the energy-efficient design, recovery, recycling, and separation of valuable metals employing ionic liquids.

Thorium Removal, Recovery and Recycling: A Membrane Challenge for Urban Mining

“…The analysis of the processes in which the minerals or waste containing thorium are processed shows that the classic technologies have material losses in the environment, which could be reduced with or through membrane techniques [ 232 , 233 , 234 , 235 , 236 , 237 , 238 , 239 , 240 , 241 , 242 , 243 , 244 , 245 , 246 , 247 , 248 , 249 , 250 , 251 , 252 , 253 , 254 , 255 ]. Thus, in the classical thorium recovery technologies, some disadvantages [ 1 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65…”

“…Recent publications are consistent and draw attention to the need to reconsider thorium as a nuclear material with a clear perspective [ 1 , 2 , 3 , 4 , 5 ] but also as an environmental polluter [ 6 , 7 , 8 ]. On the other hand, new materials usable in various analytical or technological separative techniques are also studied [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ].…”

Challenges in Using Ionic Liquids for Cellulosic Ethanol Production

“…The recyclability of ILs is one of the great advantages that these solvents have. The reuse of ILs and the generation of considerable savings in the final process of biorefineries also make it environmentally sustainable [ 60 ]. The recovery of ILs is an alternative not only to their high cost, but also to their potential toxicity after pretreatment.…”

Mechanisms of Biological Effects of Ionic Liquids: From Single Cells to Multicellular Organisms

“…Starting from molten salt electrolytes in the 1960s, we have reached the land of (almost) infinite possibilities where any property or application you can think of is possible, at least, theoretically . For example, ILs have been successfully applied in organic synthesis (both as reaction media and catalysts), − electrochemistry, − biomass conversion and biotechnology, − extraction and separation, − and many other fields. ,− …”