Extractive metallurgy

Chemistry

Metallurgy

Materials science

Sulfuric acid

Engineering

Soil science

Hydrometallurgy

Electrode

Soil water

Leaching (pedology)

Electrowinning

Electrolyte

Environmental science

Physical chemistry

Hazardous waste

Waste management

Critical Reviews in Environmental Science and Technology

Waste electrical and electronic equipment (WEEE) contains economically significant levels of precious, critical metals and rare earth elements, apart from base metals and other toxic compounds. Recycling and recovery of critical elements from WEEEs using a cost-effective technology are now one of the top priorities in metallurgy due to the rapid depletion of their natural resources. More than 150 publications on WEEE management, leaching and recovery of metals from WEEE were reviewed in this work, with special emphasize on the recent research (2015–2018). This paper summarizes the recent progress regarding various hydrometallurgical processes for the leaching of critical elements from WEEEs. Various methodologies and techniques for critical elements selective recovery (using ionic liquids, solvent extraction, electrowinning, adsorption, and precipitation) from the WEEEs leachates are discussed. Future prospects regarding the use of WEEEs as secondary resources for critical raw materials and its techno-economical and commercial beneficiaries are discussed. AbbreviationsE-WasteElectronic wasteWEEEWaste electrical and electronic equipmentCRMCritical raw materialsPCBPrinted circuit boardLCDLiquid crystal displayCRTCathode ray tubeFl. LampFluorescent lampHDDHard disk drivesLEDLight emitting diodeEUEuropean UnionUNEPUnited Nations Environmental ProgramREERare earth elementITOIndium-tin oxidePMPrecious metalNiMH batteryNickel-hydride batteryCPUCentral processing unitRAMRandom access memoryLiBsLi-ion batteriesSFLSpent fluorescent lamps

Recent advances on hydrometallurgical recovery of critical and precious elements from end of life electronic wastes - a review