In the future, left-over toner in cast-off printer cartridges could be used as building or bridge components rather than as trash, dumped in landfills and potentially damaging the environment.
One research team reports in ACS Sustainable Chemistry & Engineering that they have come up with a technique to recycle the residual powder in “empty” cartridges into iron using temperatures that match with current industrial processes.
Electronic waste is a wide category that includes everything from televisions and computers to refrigerators and ink cartridges. According to the European Toner and Inkjet Remanufacturers Association, 500 million cartridges out of the estimated 1.1 billion sold annually end up in landfills worldwide. These “empty” cartridges can have up to 8% of unused residual powder by weight and could leach compounds into the underground water sources and soil. In an attempt to reuse this electronic waste, researchers have converted this substance into gases, oils, and even an ingredient in asphalt. Currently, Vaibhav Gaikwad and colleagues are keen on developing a brand-new approach to re-use residual toner.
The researchers deposited toner powder in a furnace, heating it to 1,550 °C. This process changed the inherent iron oxide to a product that was 98% pure iron using the polymer resins within the toner powder as a source of carbon. The researchers say that this technique would be perfect for industrial applications because steel and iron are usually made at this temperature. Furthermore, heating the powder at such a high temperature prevents poisonous side products from forming, providing an eco-friendly way to recycle residual toner.
The authors received funding from the Australian Research Council’s Industrial Transformation Research Hub. Vaibhav Gaikwad got funding for the New Generation Network fellowship from the University of New South Wales Sydney and the Australia India Institute.