An Innovative Method for the Extraction of Metal from Waste Cathode Ray Tubes through a Mechanochemical Process Using 2-[Bis(carboxymethyl)amino]acetic Acid Chelating Reagent

Abstract

To minimize electronic waste and reduce the environmental impact of hazardous metals, a new greener approach has been developed for the extraction of lead and barium metals from waste cathode ray tube (CRT) glass. The process steps comprise an initial mechanical activation of CRT funnel glass and then wet ball milling of the funnel glass powder using the metal chelate reagent 2-[bis(carboxymethyl)amino]acetic acid (NTA) and water at room temperature. After the mechanochemical treatment, the desired ≳99 mass % of lead and barium metals contained in the funnel glass powder was extracted as a metal–NTA species and pure nonleaded SiO2 glass material from the funnel glass matrix. The separation was accelerated by the ball-milling atomization and high stability constant of the metal–NTA species. After separation, the maximal amounts of lead and barium ions (∼99 mass %) were obtained as PbSO4 and BaSO4, respectively, with the addition of ferric sulfate. Notably, the developed method does not require heat and doe...