‘98% efficiency’: Can you extract ‘Silver’ from a dead solar panel?
Produced by: Tarun Mishra Designed by: Manoj Kumar
New Silver Recovery Method for Solar Panels
A multi-disciplinary team of chemists, metallurgists, and engineers has developed a highly efficient technique to recover silver from decommissioned solar panels, according to their recent study published in *Environmental Technology & Innovation*.
Challenge in Solar Panel Recycling
While components like iron, steel, and aluminium in solar panels are relatively easy to recycle, recovering silver—used in electrical circuits—has been more difficult. This new method addresses this challenge, improving silver recovery rates significantly.
Innovative Chemical Process
The developed process utilizes base-activated persulfate combined with ammonia to extract silver. Persulfate acts as the oxidizing agent, producing copper oxide that prevents the leaching of copper, which is also present in solar panels.
Experimental Methodology
Researchers experimented with various concentrations of ammonia and persulfate, while controlling factors such as stirring speed and temperature. They identified optimal conditions of 0.5 M ammonia and 0.2 mol per litre potassium persulfate, with a reaction time of one hour.
High Efficiency Achieved
Under these conditions, the process successfully separated 85% of the silver from a sample. Further refinement through electrodeposition-redox replacement increased the recovery rate to 98.7%.
Confirmation Through Microscopy
The team used a scanning electron microscope to confirm the high purity of recovered silver particles, validating the effectiveness of their method.
Impact on Solar Panel Waste Management
This new technique offers a promising solution for the environmental challenge of disposing of old solar panels, enhancing the sustainability of solar energy by making the recovery of valuable materials more efficient.