Scientists presented a technology for converting polypropylene into fairly pure gasoline and diesel fuel with supercritical water.
About a quarter of all plastic products are made from polypropylene, ranging from toys and medical devices., ending with packages for chips. Every year, 75 million tons of such waste ends up in landfills. However, chemists at Purdue University have found a way to turn these mountains of rubbish into fuel that can be used. for refueling cars.
Researchers used supercritical water, a special state of matter in which the distinction between the liquid and gas phases disappears. To do this, they heated H2O to a temperature of 380-500 °C at a pressure of 23 MPa, which is about 230 times higher than normal atmospheric.
91% of purified polypropylene waste placed in such conditions for 0.5-6 hours turn to oil. Conversion time depends on temperature. For example, at 450 °C takes less than 60 minutes. In this case, 80-90% of the components of the resulting mass had the same boiling point range as naphtha, and their specific heat of combustion was 48-49 MJ / kg. By-products of this process include gasoline, diesel oils and feedstocks for other chemicals..
This way of transformation suitable for recycling 90% of the world’s waste of polypropylene into fuel, and compared with burning and mechanical processing it potentially more energy efficient and reduces emissions greenhouse gases. In addition to the environmental benefits of reducing plastic pollution, you can also earn money by selling fuel. Therefore, chemists hope that the technology they have developed will soon be implemented on an industrial scale.
We also previously reported that researchers from the University of Pittsburgh have developed a nanomaterial with an organometallic structure that is able to absorb carbon dioxide and hydrogen from the air, creating useful chemicals from them.
text: Ilya Bauer, photo: Purdue University
Sia – Soon We’ll Be Found