Selective thermal recycling for graphene growth on natural substrates: A comparative study on life cycle assessment, energy consumption, and mechanical performance in recompounding

Abstract

Manufacturing of carbon‐based materials from waste thermoplastics is a keystone to reduce adverse environmental impacts. There are numerous attempts for sustainable graphene manufacturing from various waste sources by thermal treatment but there is no clear distinction on the effective conversion process by addressing reliable CO2 footprints. This study provides a comprehensive benchmarking study on the conversion of waste polypropylene plastics coming from yogurt containers into graphene on the substrate of talc by applying two upcycling techniques of catalytic carbonization (CC) and flash pyrolysis (FP) by comparing energy and speed of the processes and a dimensional stability and physical characteristics of the produced graphene substances by adopting a comparative life cycle assessment. FP led to the sphericalization of graphenes due to fast dehydration, cross‐linking, and carbonization of aromatic structures. On the other hand, gradual heating in CC caused the formation of tubular‐like graphene structures. In addition, FP became advantageous by resulting in 52% of CO2 emission compared with CC process. On the other hand, graphenes separated from talcs exhibited a remarkable 70% reduction in global warming potential compared with conventional graphene production from graphite. In order to complete the value chain and circularity, the mechanical performance of two different hybrid additives produced by selective thermal recycling in recompounding with copolymer polypropylene was examined, and additives from CC enhanced the flexural and tensile properties two times better than the one from FP. With this study, it becomes possible to compare analysis of graphene growth on natural substrates by exploring life cycle assessment, energy consumption, and mechanical performance with selective thermal recycling and recompounding.

Turning CO2 into sustainable graphene: a comprehensive review of recent synthesis techniques and developments

“…Despite these advancements, achieving precise control over graphene properties, including layer number, morphology, crystallinity, and size, while overcoming challenges in CO 2 conversion, remains critical for sustainable graphene production. Nevertheless, recent researches demonstrates promising strides in optimizing methods and controlling graphene growth, offering potential solutions for advancing this field towards sustainable and efficient graphene manufacturing [36,56,165]. For instance, Bayrak-Baskan et al optimized pyrolysis method at a suitable temperature and demonstrated elevated temperatures resulting in higher graphene yields by facilitating the breaking of C-H and C-C bonds of waste plastic as carbon source [165].…”

“…Nevertheless, recent researches demonstrates promising strides in optimizing methods and controlling graphene growth, offering potential solutions for advancing this field towards sustainable and efficient graphene manufacturing [36,56,165]. For instance, Bayrak-Baskan et al optimized pyrolysis method at a suitable temperature and demonstrated elevated temperatures resulting in higher graphene yields by facilitating the breaking of C-H and C-C bonds of waste plastic as carbon source [165]. Furthermore, adjusting substrate type, size, and surface composition enables precise control over graphene growth dimensions, offering an opportunity to utilize waste materials as potential carbon sources.…”