TU-TESL

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Chemists at Singapore's Nanyang Technological University have found a new way to use sunlight to turn plastic waste into valuable chemicals, foreign media reported. In the lab, the team mixed plastic and catalyst into a solvent that uses light energy to convert dissolved plastic into formic acid, a chemical that can be used for fuel power generation. The team, led by soo Han Sen, an assistant professor at the school of physics and mathematics at Nanyang University of technology, used cheap, non biocompatible vanadium, an aluminum alloy commonly used in cars and airplanes, as a catalyst. However, the vanadium based catalyst dissolves in a solution containing non biodegradable consumer plastics (such as polyethylene) and is exposed to artificial sunlight. Within six days, it will decompose the carbon carbon bond in the plastic. When the catalyst is dissolved in a solution containing non biodegradable consumer plastics (such as polyethylene) and exposed to artificial sunlight, the carbon carbon bond in the plastic will be broken down within 6 days. The process converts polyethylene into formic acid, a natural preservative and antibacterial agent, which can be used in power plants and battery cars to produce energy. "Our goal is to develop sustainable and cost-effective ways to use sunlight to produce fuel and other chemicals," said Professor soo. This new chemical treatment method is the first one to completely degrade non biodegradable plastics such as polyethylene by using visible light and heavy metal free catalyst. " In Singapore, most of the plastic waste is burned, which will produce greenhouse gases such as carbon dioxide, and a large number of burned ashes will be transported to semakau landfill. It is estimated that there will be no more space in the landfill by 2035. The research and development of innovative zero waste solutions, such as the use of environmental protection catalysts to turn waste into resources, is part of Nanyang University of technology's vision for the sustainable development of its intelligent campus. The vanadium based catalyst is supported by organic groups and uses light energy to drive chemical reactions. It is called photocatalyst. Photocatalysts can realize chemical reactions powered by sunlight, while most of the reactions in industry require heat, which is usually provided by burning fossil fuels. Other advantages of the new photocatalyst include low cost, abundant reserves and environmental protection, which is different from the common catalysts made of expensive or toxic metals such as platinum, palladium or ruthenium. Although scientists have tried to use other methods to convert waste plastics into useful chemicals, many of them require a lot of poor reagents or too many steps to achieve large-scale transformation. One is the use of photocatalysis, which combines plastics with water and sunlight to produce hydrogen, but this method requires the use of catalysts containing toxic heavy metal cadmium. Other methods require the treatment of plastics with dangerous chemical solvents. Most plastics are non biodegradable because they contain a very inert chemical bond called a carbon carbon bond, which is not easily broken down if not at high temperature. The new vanadium based photocatalyst developed by the research team of Nanyang University of science and technology is specially designed to break down such chemical bonds. By attaching to a nearby chemical group called alcohol group and using the energy absorbed from the sun, it can unlock the molecules, just like opening the zipper. The new vanadium based photocatalyst developed by the research team of Nanyang University of science and technology is specially designed to break down such chemical bonds. By attaching to a nearby chemical group called alcohol group and using the energy absorbed from the sun, it can unlock the molecules, just like opening the zipper. Now, the team is improving the process to allow plastics to decompose to produce other useful chemical fuels, such as hydrogen.