FOR IMMEDIATE RELEASE

ACS News Service Weekly PressPac: Wed Mar 14 11:43:07 EDT 2018

An eco-friendly alternative to recycling e-waste

Materials and Energy Recovery from E-Waste Plastics
ACS Sustainable Chemistry & Engineering

As consumers toss aside old cell phones, tablets and laptops to keep up with the latest technology, landfills are becoming full of the old devices. To address this buildup, scientists are attempting to recover valuable plastics from this electronic waste, or “e-waste.” Now, one group reports in ACS Sustainable Chemistry & Engineering that they have found an eco-friendly alternative to current methods.

In 2009, U.S. consumers discarded 2.37 million tons of e-waste, according to the U.S. Environmental Protection Agency. This type of refuse is a broad category that includes everything from phones and video game consoles to refrigerators and televisions. These devices contain valuable plastics, such as polycarbonates. In an effort to reduce the amount of e-waste accumulating in landfills and recover the valuable polymers, researchers have explored different extraction methods. Current approaches can include the use of chlorinated substances, such as dichloromethane (DCM), that are toxic, pricey and volatile. Sriraam R. Chandrasekaran, Brajendra K. Sharma and colleagues wanted to explore an alternative solvent called N-methyl-2-pyrrolidone (NMP) that would be more friendly to the user and the environment.

Cell phone plastics typically contain a mixture of polycarbonate and polyamide. In large-scale experiments, the researchers found that DCM and NMP recovered 87 percent and 89 percent of the polycarbonate from cell phone plastic, respectively, and the NMP could be reused at least one more time without losing efficiency. But some e-waste contains more complex mixtures that would require multiple solvents and a lot of energy to recycle. In that case, the team suggests that pyrolysis, or heating the material to high temperatures, would be a better alternative. They showed that the amount of a mixture of four e-waste plastics was reduced by about 40 percent with pyrolysis.

The authors acknowledge funding from HOBI International, Inc. and the Hazardous Waste Research Funds of Illinois Sustainable Technology Center.

Note: ACS does not conduct research, but publishes and publicizes peer-reviewed scientific studies.

Recycling electronic waste is made easier with a new eco-friendly method.
Credit: Photographee.eu/Shutterstock.com