|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Deriving Value from Challenging Waste Streams: Recycling and Sustainability Joint Session
||Novel Technologies for Technospheric and Urban Mining of Rare Earth Elements from Phosphogypsum, Red Mud, Hybrid Car Batteries, and Wind Turbine Magnets
||Yuxiang Yao, Sable Reid, Mugdha Walawalkar, Nina Farac, Feixiong Zhang, Brittny Carter, Gisele Azimi
|On-Site Speaker (Planned)
Some rare earth elements (REEs) are classified under critical materials, i.e., essential in use and subject to supply risk, due to their increasing demand, monopolistic supply, and environmentally unsustainable mining practices. To tackle the REE supply challenge, new initiatives have been started focusing on their extraction from alternative secondary resources. This study puts the emphasis on technospheric mining of REEs from phosphogypsum (byproduct of fertilizer industry) and red mud (byproduct of aluminum industry) as well as urban mining of REEs from nickel metal hydride batteries used in hybrid vehicles and neodymium-iron-boron magnets used in wind turbines. Several processes including direct acid leaching, supercritical fluid extraction, and microwave pretreatment are investigated. The proposed waste valorization processes have the double advantage of generating strategic materials from otherwise a waste stream and simultaneously providing environmental benefits through reducing the amount of waste and costs associated with constructing and maintaining storage facilities.