Future carbon footprint of municipal plastic waste treatment in china across the nexus of energy transition, bio-economy, and chemical recycling

Abstract The sustainable life-cycle management of plastics has become an international consensus. Plastic pollution primarily arises during the post-consumer solid waste management phase, particularly from mismanaged disposal and landfilling. Municipal waste incineration offers an economically viable solution to address plastic pollution, but its significant CO 2 emissions challenge its sustainability in the context of global climate goals. To provide quantitative strategies for low-carbon plastic pollution management, this study analyzes the carbon footprint of municipal plastic waste in China across various mitigation pathways, including energy transition, bio-economy, and chemical recycling (CR). The results reveal that under a high-carbon power grid and business-as-usual scenario, plastic waste generation of 53.66 MT in 2050 would result in a carbon footprint of 35.79 MT CO 2 -eq. The introduction of 50% bio-based plastics shows modest reductions (8.82 MT CO 2 -eq) due to the inclusion of biogenic CO 2 emissions. Increasing the recycling rate to 60% through a combination of mechanical recycling and CR achieves limited reductions (17.61 MT CO 2 -eq) due to the energy-intensive CR process. However, under low-carbon grid conditions, it can reach a negative carbon footprint of −21.52 MT CO 2 -eq with higher recycling rates owing to avoided plastic incineration and recovered materials. This study provides a quantitative framework for evaluating plastic waste management strategies under various decarbonization scenarios. It highlights the importance of integrating advanced recycling technologies, bio-economy, and sustainable energy systems for formulating data-driven policies aligned with climate action and plastic pollution mitigation.