I-Corps: Sorting of Metals for Electronics Recycling

Cuny Queens College, Flushing NY

Investigators

Abstract

The estimated value of precious metals from consumer-electronic e-waste (gold, palladium, silver, copper) is $500M/yr and growing; yet only 20% of e-waste is collected and separated for recycling, leaving $400M/yr of precious metals in landfills. The current precious metals recycling processes primarily include manual sorting, pyrolysis, hydrolysis, scrapping and smelting that are energy intensive or involve hazardous chemicals such as nitric acid and chlorine gas. Regions are beginning to implement regulations mandating the responsible disposal of e-waste, thus further spurring market growth and the need for different technologies. Knowledge of the distinct optical forces and chemical environments that control the hydrodynamics of nanoparticles could assist with the separation and sorting of metal nanoparticles. Selective control over the surface-enhanced mechanical effects on different metals would have applications towards the clean-up of chemical waste and the extraction or recycling of metal particulates. This team has developed a method for optical separation and sorting that could be controlled remotely via microfluidic channels in a safe aqueous environment, using energy-efficient lasers or LEDs. The proposed product is a plug-and-play solution for e-waste pre-processing companies using an optical response to separate different materials. The proposed technology will be more cost-effective than traditional smelting, easier to operate, will use less energy and can operate as a smaller, scalable system.