# Extraction of Yttrium from Waste: Analysis of Hydrometallurgical Processing by Organic Acids and Life Cycle Assessment

## TL;DR

This study explores using organic and inorganic acids to recover yttrium from old fluorescent lamps and evaluates the environmental impact of the process.

## Contribution

The study introduces a feasible method for yttrium recovery from e-waste using organic acids and evaluates its environmental impact via LCA.

## Key findings

- High yttrium recovery rates were achieved using organic and inorganic acids, with citric acid (C6H8O7) reaching 86.7% and acetic acid (C2H4O2) reaching 100%.
- Leaching with organic acids showed higher environmental impact due to their production and disposal methods.
- The process is a feasible alternative for large-scale yttrium recovery and supports sustainable e-waste recycling.

## Abstract

The increasing demand for rare earth elements has driven
the search
for efficient and sustainable recovery methods. Obsolete fluorescent
lamps represent a significant secondary source of Y that can greatly
contribute to the circular economy and the preservation of natural
resources. With the gradual depletion of primary Y reserves and the
rise in e-waste generation, the development of eco-friendly and economically
feasible recovery techniques has become crucial. Additionally, strict
legislation regarding the disposal of e-waste strengthens the need
to improve recycling processes. This study aims to investigate the
leaching of Y from obsolete fluorescent lamps by organic (C6H8O7, C2H4O2, and C2H5NO2) and inorganic acids
(HNO3). We also seek to assess the environmental impact
of this process through life cycle assessment (LCA). Leaching steps
were performed with different acid concentrations, followed by selective
precipitation with C2H2O4 for Y recovery.
LCA was applied to evaluate the environmental impacts and identify
critical points in the process. A high Y recovery rate (78.8% for
C2H5NO2, 86.7% for C6H8O7, 100% for C2H4O2, and 95% for HNO3) was obtained with precipitation (C2H5NO2 and C6H8O7 liquor). Our environmental assessment revealed that
leaching with organic acids presents a higher environmental impact
due to production and disposal methods. The study demonstrated that
it is possible to leach Y efficiently from fluorescent lamps using
organic acids. The process may be a feasible alternative for large-scale
Y recovery, improving organic acid production, and contributing to
the sustainable recycling of e-waste and promoting the circular economy.