Systematic generation and targeting of chemical recycling pathways: A mixed plastic waste upcycling case study

Abstract The current concerns regarding plastic waste accumulation and resource scarcity are leading to a waste and resource management paradigm shift, and consequently the number of alternatives for treating and upcycling waste keeps increasing. Here, we develop a new approach to determine the most promising processes or process routes to valorize waste by seeking the best environmental and economic performance. Due to the large number of alternatives, we designed this method to select a certain number of choices prior to further assessment and optimization. As a case study, we chose the treatment of mixed plastic waste. Using the methodology, we are able to select a few alternatives among a large number of different alternatives as the most promising towards closing material loops. The use of graph theory and branch and bound algorithms allows building an efficient framework for this purpose.