'Zero-waste smartphones in the offing'

Scientists have perfected a process to efficiently separate fibreglass and resin - two of the most commonly discarded parts of a cell phone, bringing zero-waste smartphones closer to reality.

It is one of the first processes to use simple techniques like gravity separation to cleanly lift organic resins from inorganic fibreglass, researchers said.

"Discarded cellphones are a huge, growing source of electronic waste, with close to two billion new cellphones sold every year around the world and people replacing their phones every few years," said Maria Holuszko, a professor at the University of British Columbia in Canada.

"The challenge is to break down models that can no longer be reused into useful materials - in a way that does not harm the environment,' said Holuszko, who led the study published in the journal Waste Management.

Most e-waste recycling firms focus on recovering useful metals like gold, silver, copper and palladium, which can be used to manufacture other products.

However, nonmetal parts like fibreglass and resins, which make up the bulk of cellphones' printed circuit boards, are generally discarded because they are less valuable and more difficult to process.

"They are either fed to incinerators or become landfill, where they can leach hazardous chemicals into groundwater, soil and air," said Holuszko.

In collaboration with PhD student Amit Kumar, Holuszko developed a process that uses gravity separation and other simple physical techniques to process cellphone fibreglass and resins in an environmentally neutral fashion.

"The key here is gravity separation, which efficiently separates the fibreglass from the resin by using the differences in their densities," said Kumar.

"The separated fibreglass can then be used as a raw material for construction and insulation. In the future, if we can find a way to improve the quality of the recycled fibreglass, it may even be suitable for manufacturing new circuit boards," he said.