Applicability of paper deinking process for silver separation and concentration from a paper-based printed...

Area of Science:

• Materials Science
• Environmental Science
• Chemical Engineering

Background:

• Paper-based printed electronics (PE) offer a sustainable alternative to plastic electronics.
• The end-of-life management and recyclability of PE are not well understood.
• PE, primarily paper, may enter conventional paper recycling streams.

Purpose of the Study:

• To investigate the end-of-life processing of silver-based RFID antennas within a paper recycling deinking line.
• To assess the suitability of traditional paper recycling unit operations for removing silver contaminants.
• To determine the efficiency of silver separation using screening, centrifugal cleaning, and flotation.

Main Methods:

• A silver-based RFID antenna prototype was disintegrated via pulping.
• Separation efficiency of silver was evaluated using screening, centrifugal cleaning, and flotation.
• The influence of paper substrate and experimental conditions on silver detachment and separation was analyzed.

Main Results:

• Optimized pulping effectively detached silver particles from paper fibers.
• Separation efficiency varied by unit operation: screening < flotation < centrifugal cleaning.
• Flotation showed poor efficiency (20-40%), while centrifugal cleaning achieved high silver separation (70-99.9%).

Conclusions:

• Conventional paper recycling lines can be adapted for PE recycling.
• Optimizing unit operation conditions is crucial for efficient silver separation from PE waste.
• Centrifugal cleaning demonstrates significant potential for removing silver contaminants in PE recycling.