Recovery of yttrium from obsolete fluorescent lamps

• Grant number: 23/15490-5
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: December 18, 2023
• End date: February 28, 2024
• Field of knowledge: Engineering - Chemical Engineering
• Principal Investigator: Denise Crocce Romano Espinosa
• Grantee: Luan Matheus da Silva Alvarenga
• Supervisor: Mentore Vaccari
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Università degli Studi di Brescia, Italy
• Associated to the scholarship: 22/16500-1 - Recovery of rare-earth elements from obsolete fluorescent lamps, BP.IC

Abstract

With technological advances, the use of rare earth elements has intensified in recent decades. The applications of these elements stand out in electronic information, metallurgy, the petrochemical industry, energy and environment, and national defense. The main issue when mining rare earth elements lies in their low ore concentration. Thus, the mining process becomes more expensive and sometimes commercially unviable. Therefore, recovery from urban waste can become a viable alternative. One of the advantages of regaining rare earths from urban waste is that the formation of radioactive by-products associated with mining, such as thorium and uranium, can be avoided. Among the devices with one or more rare earth elements in their composition are fluorescent lamps. The phosphor layer present in lamps corresponds to approximately 3% of the total lamp components. In this study, the investigation of a yttrium recovery route from the leachate using organic acids from fluorescent lamp powder will be carried out. For this purpose, the feasibility of yttrium precipitation from the leachate using oxalic acid with varying excess percentages will be assessed. Subsequently, the purity of the oxide after calcination of the precipitate will be evaluated.