Research Projects

In recent years, there has been a huge demand for Rare-earth elements (REEs), including 15 lanthanides, scandium, and Yttrium, respectively. REEs are used for several applications, such as permanent magnets, fluorescent materials, laser crystals, ceramics, alloys, catalysts, superconductors, batteries, etc. Fly ash, the industrial waste product from the thermal power plant, is a rich source of REEs and other precious elements. This project focuses on using fly ash to extract REEs as an alternative to monazite minerals. In industries, REEs are extracted by solvent extraction, which involves several steps using strong acids and alkalis. Volatile organic solvents are used for extraction, which is toxic, flammable, or volatile and has high disposal costs. Considering the above facts, Ionic liquids are identified as the green chemicals for REE extraction. Aqueous immiscible ILs are used for the chemical extraction process. The application of ILs, reduces the sequence of steps and time, disposal of toxic chemicals, etc. The ionic liquids contain a large electrochemical window. It also contains both anions and cations, which can be functionalized as per the affinity towards the elements. This property is expected to give the path to extract REEs from fly ash by electrodeposition. In this project, the feasibility study on the electrodeposition of REEs using betainium bis- (trifluoromethylsulfonyl) imide [Hbet][Tf2N]’s ionic liquid will be carried out, which has thermomorphic behavior with water. In addition, the imidazolium cation group with fluoride and chloride-based anions containing ILs will be explored. The project work involves following studies as per the timeline. Selection of fly ash from thermal power plants located in a different state of India containing high content of REEs. Leaching of fly ash with an alkaline solution to break the aluminosilicate glass phase encapsulated REEs. Analysis of concentration of rare earth elements present in the leached alkaline solution by ICP-OES and ICP-MS. An alkali leach solution containing REE and ionic liquid such as [Hbet][Tf2N] to study the feasibility of electrodeposition of REE from the IL medium. Optimization of parameters such as temperature, pH, rare earth extractant, and ionic liquid ratio suitable for electrodeposition. Optimization of conditions such as conductivity, voltage, area of deposition, cathode /anode ratio, and selection of suitable anodes and cathodes etc. for electrodeposition of REE from extractant/ ionic liquid electrolyte. Analysis of yield and purity of the electrodeposited rare earth element. Stripping of REE deposited on the cathode.Regeneration of ionic liquid by acid leaching process for further use. Comparisons of yield and purity of electrodeposited REEs with the solvent extraction process. Exploring other imidazole-based ionic liquids for electrodeposition. Compilation of results and preparation of reports.