Sustainable Recycling and Valorization of Mixed Plastic Waste to High-Value End Products

Anokwu, Jerome

Abstract

Mixed post-consumer plastic waste (MPW) poses one of the greatest waste stream challenges worldwide as plastics take 500-1000 years to degrade. The world generates 320 million tonnes of MPW yearly, which is expected to triple by 2050. A 9% annual increase in MPW generation suggests that besides irrational production, improper usage and disposal of plastics, conventional landfilling, incineration, and recycling may be inadequate to handle MPW. With the world in danger of being overwhelmed by plastic pollution, a sustainable solution is essential. Pyrolysis, which is the thermal breakdown of materials at elevated temperatures in inert environment could offer viable solutions to handling MPW with the advantage of producing useful end-products. In contrast to conventional methods, pyrolysis has low carbon footprint and can handle commingled and contaminated wastes. In this study, 3000g of MPW containing High-Density Polyethylene-33.3%, Low-Density Polyethylene-33.3%, Polypropylene-16.7%, Polystyrene-16.7% was pyrolyzed at 350-450OC in a batch reactor for 180 mins. The products of the pyrolysis were oil-56wt%, gas-41.5wt% and char-2.5wt%. Physical properties of the oil were evaluated, with results suggesting that it has comparable properties to diesel and gasoline. This study demonstrate that pyrolysis can overcome the major limitations of conventional recycling with the ability to process mixed plastic waste. Pyrolysis could significantly reduce waste generation as a 97.5% mass reduction of MPW was achieved. MPW pyrolysis could lead to production of fuel which is a valuable resource recovery. This study would evaluate the chemical properties of the oil and char to determine their chemical composition and potential application.

• Online Publication Date: Jul 2, 2023
• Publication Date: Jul 2, 2023
• Deposit Date: Jan 23, 2025
• DOI: https://doi.org/10.17866/rd.salford.23608323.v1
• Publisher URL: https://salford.figshare.com/articles/poster/Sustainable_Recycling_and_Valorization_of_Mixed_Plastic_Waste_to_High-Value_End_Products/23608323
• Collection Date: Jul 2, 2023