The photo is sourced from celsia.io
Water in its ordinary state does not have enough properties to decompose plastic. To remove this limitation, the authors of the study placed some water in a closed system, heated it to 373 degrees Celsius and compressed at a pressure of over 217 atmospheres. Under such conditions, the substance reached a critical point and turned into a fluid state, remaining simultaneously a liquid and a gas. This not only destroyed the most complex chemical chains of industrial waste, but also prevented them from sintering back together, creating even more complex waste. As a result, the water in the experiment became an effective and yet an environmentally friendly solvent.
The new approach does not require pre-sorting and purifying raw materials and makes it possible to receive a finished product at the output. The available plastic recycling technologies, for example, through combustion, produce purified secondary pellets, while the result of our solution is an initial petroleum product that can be used for fuel production. The proposed solution separates complex waste into simple components and does not require a separate market, as with secondary raw materials. The output is various types of fuel: gasoline, kerosene, diesel, totaling up to 85% of the feedstock total volume,” Perm Polytech quotes Oleg Ivanov, the project scientific director.
Petroleum products are not the only type of raw materials that can be obtained by recycling plastic, hydrogen is another product: For this purpose, plastic waste is shredded and placed into a special thermal chamber, where under the impact of high temperatures, small pieces turn into a viscous alloy, then vaporised into synthesis gas being a mixture of methane, hydrogen and carbon monoxide. Once dried, the synthesis gas can be used for electricity generation as well as hydrogen production through steam conversion. This solution was proposed by Powerhouse Energy.