Human ingenuity can deal with plastic recycling!
What would humanity do without plastics?
What are the options:
- Invent better materials to replace plastics
- Develop recycling methods
Don't believe the decades old alarmism and hysteria about plastics! It's case of plastophobia!
"... many ... common products are composed of polystyrene, a type of plastic that makes up a third of landfill waste worldwide. ...
discovered a new path for polystyrene waste that includes being upcycled into benzoic acid, a chemical with wide commercial demand, through a mild process that uses light, an oxygen-rich environment and an abundant iron-based catalyst. The reaction can even take place in a sunny window. ...
Moreover, the process is tolerant of additives inherent in a flow of consumer waste, including dirt, dyes and other types of plastics. ...
The researchers found that optimized conditions require a polystyrene sample in acetone exposed to LED light in an oxygen-rich environment, using an iron chloride catalyst for 20 hours. In the optimized process, PS broke down to 23% benzoic acid. Other products included smaller plastic molecules that can be repurposed in other ways. ...
To demonstrate scalability and potential commercial application, the researchers created a setup with two syringe pumps and two LED lamps in a 3D-printed photoreactor. The efficiency of the breakdown process at the large scale was similar to that in small batches. ..."
discovered a new path for polystyrene waste that includes being upcycled into benzoic acid, a chemical with wide commercial demand, through a mild process that uses light, an oxygen-rich environment and an abundant iron-based catalyst. The reaction can even take place in a sunny window. ...
Moreover, the process is tolerant of additives inherent in a flow of consumer waste, including dirt, dyes and other types of plastics. ...
The researchers found that optimized conditions require a polystyrene sample in acetone exposed to LED light in an oxygen-rich environment, using an iron chloride catalyst for 20 hours. In the optimized process, PS broke down to 23% benzoic acid. Other products included smaller plastic molecules that can be repurposed in other ways. ...
To demonstrate scalability and potential commercial application, the researchers created a setup with two syringe pumps and two LED lamps in a 3D-printed photoreactor. The efficiency of the breakdown process at the large scale was similar to that in small batches. ..."
From the abstract:
"Chemical upcycling of polystyrene into targeted small molecules is desirable to reduce plastic pollution. Herein, we report the upcycling of polystyrene to benzoyl products, primarily benzoic acid, using a catalyst-controlled photooxidative degradation method. FeCl3 undergoes a homolytic cleavage upon irradiation with white light to generate a chlorine radical, abstracting an electron-rich hydrogen atom on the polymer backbone. Under the oxygen-rich environment, high MW polystyrene (>90 kg/mol) degrades down to <1 kg/mol and produces up to 23 mol % benzoyl products. A series of mechanistic studies showed that chlorine radicals promoted the degradation via hydrogen-atom abstraction. Commercial polystyrene degrades efficiently in our method, showing the compatibility of our system with polymer fillers. Finally, we demonstrated the potential of scaling up our approach in a photoflow process to convert gram quantities of PS to benzoic acid."
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