• It takes hundreds of years for polystyrene (thermocol being a widely used form of it) to be degraded in the natural environment. But in a solution of orange peel extract, it dissolves almost instantly – without the aid of external heat, pressure or acid.
• Now a group of researchers from the Indian Institute of Technology (IIT), Hyderabad, has demonstrated a cheaper, low-energy, and green way of recycling polystyrene and low density Styrofoam (a form of expanded polystyrene) using orange peel extract. They have a working prototype, and a pilot-scale machine to recycle polystyrene is under construction.
• The necessary fruit extract can be obtained simply by squeezing the orange peels.
• Currently, only about 12% of polystyrene waste gets recycled, and nearly a third is dumped in landfills. Worldwide, about 31 million tonnes of citrus fruits are produced annually, and 50% of it is waste in the form of citrus peel. The fruit juice industry in particular generates large quantities of citrus peel waste.
• Limonene, which is one of the components of the extract, is capable of dissolving polystyrene but is currently not used for this purpose.
• “Compared with limonene, the whole extract can dissolve polystyrene five times more.
• The project has received financial support of Rs.37 lakhs from the Technology Development Board, Department of Science and Technology (DST) under the Waste Management Programme.
• The innovation also won a gold medal in the recently concluded World Invention and Innovation Forum (WIIF) 2017 in Guangdong, China.
• The process basically involves dissolving polystyrene in the citrus extract and drawing it into fibres using wet/solution spinning. The fibre is then turned into a non-woven fabric of 1 sq. foot size. Since fabric made of recycled polystyrene is naturally oil-loving, it can be used for day-to-day household cleaning in kitchens, and also for large-scale removal of oil-spills.
• “Using the orange peel extract to dissolve polystyrene will not change the chemical composition, and so will not make polystyrene into a biodegradable product. What this process does is to extend the use and life cycle of polystyrene waste material,

Source:TH