Metallurgical processes for the recovery and recycling of lanthanum from various resources—A review

• This paper reviews the metallurgical processes to recover La from various sources.
• Bauxite, optical glass, and Ni-MH battery serve as recent secondary resources of La.
• Monazite, fluorocarbonate ores, and phosphate rock are the most promising La resource.
• Combined hydro/pyro-metallurgical processes are commonly used for La recovery.
• A brief discussion for selective separation of La from actual solutions is included

Various processes for the recovery of lanthanum from metallurgical and non-metallurgical resources are reviewed. Lanthanum is present as a major constituent of monazite, fluorocarbonate ores, bauxite and associated residues, tailings and waste liquors of rare earths, aluminium, etc. Phosphate rock, optical glasses and Ni-MH batteries serve as the most recent and high concentration secondary resources of lanthanum. This review discusses the various methods of hydro-/pyro-metallurgical origin, leaching, solvent extraction, precipitation and other pre-treatment options for lanthanum recovery. A separate section on recovery of lanthanum by selective biosorption from various model and actual solutions is also included. The need to develop new extraction systems with high lanthanum selectivity in the areas of leaching and solvent extraction are probable improvement trend for the future.