Scale‐up and Sustainability Evaluation of Biopolymer Production from Citrus Waste Offering Carbon Capture and Utilisation Pathway

Abstract

Poly(limonene carbonate) (PLC) has been highlighted as an attractive substitute to petroleum derived plastics, due to its utilisation of CO2 and bio‐based limonene as feedstocks, offering an effective carbon capture and utilisation pathway. Our study investigates the techno‐economic viability and environmental sustainability of a novel process to produce PLC from citrus waste derived limonene, coupled with an anaerobic digestion process to enable energy cogeneration and waste recovery maximisation. Computational process design was integrated with a life cycle assessment to identify the sustainability improvement opportunities. PLC production was found to be economically viable, assuming sufficient citrus waste is supplied to the process, and environmentally preferable to polystyrene (PS) in various impact categories including climate change. However, it exhibited greater environmental burdens than PS across other impact categories, although the environmental performance could be improved with a waste recovery system, at the cost of a process design shift towards energy generation. Finally, our study quantified the potential contribution of PLC to mitigating the escape of atmospheric CO2 concentration from the planetary boundary. We emphasise the importance of a holistic approach to process design and highlight the potential impacts of biopolymers, which is instrumental in solving environmental problems facing the plastic industry and building a sustainable circular economy.

Bibliographic mapping of post-consumer plastic waste based on hierarchical circular principles across the system perspective

“… [ 42 ] X PET recycling with enzymes as catalyst. [ 47 ] X Bio-derived polymer from citrus waste. [ 55 ] X Household plastic contamination.…”

“…Two texts focused on bioplastic as a substitute for fossil-based materials in terms of its chemical functionalities [ 170 ], upcycling process [ 16 ], and low environmental impact with particular regard to the food packaging applications of PLA material [ 194 ]. Extensive research into bioplastics focuses on the development of bioplastic production, namely; bio-derived polymer extracted from citrus waste [ 47 ] and sludge cellulose plastic composite (SPC) [ 258 ]. Furthermore, bioplastic from microalgae cultivation exploits agricultural run-off and urban wastewater as feedstock [ 232 ], cosmetic packaging made from bio-based polymer [ 30 ], converts biomass into bio-plastic [ 215 ], and combines 3D printing with biomaterials [ 238 ].…”

“…The literature on the development of bio-based plastic polylactic acid (PLA) and polyhydroxyalkanoates (PHA) focused on its substitution and commercial viability [ 217 ]; compounding food waste with PLA [ 29 ]; together with its standardized labeling; sorting; coordinated regulation [ 177 ]; production technologies; challenge; and future opportunities [ 166 ]. Popular research bioplastic research focuses on the development of bioplastic production, namely; bio-derived polymer from citrus waste [ 47 ]; PLA from agricultural waste [ 6 ] and sludge cellulose plastic composite (SPC) [ 142 ]. Other topics include: bioplastic produced by microalgae cultivation using agricultural runoff and urban wastewater as feedstock [ 232 ]; cosmetic packaging made from bio-based polymer [ 30 ]; converting biomass into bio-plastic [ 215 ]; and combining 3D printing with biomaterials [ 238 ].…”

Recent Development of Polyhydroxyalkanoates (PHA)-Based Materials for Antibacterial Applications: A Review

“…In this case, the soil is used to “cultivate bio plastique” instead of food. In other words, the development of PLA and all the other biopolymers require extensive exploitation of feedstock, thus posing severe ethical doubts. , To overview some recent analyses, the production and commercialization of PLA are expected to decelerate in the foreseeable future . Recently, polyhydroxy­alkanoates (PHAs) have been recognized as the new generation of bioplastics as their production is based on the micro­organism fermentation.…”

Unlocking the Processability and Recyclability of Biobased Poly(limonene carbonate)

“…The potential of PLimC for applications was shown by Koning et al for coatings , and by us for membranes . Interestingly, even the evaluation of the availability of limonene and life cycle assessments of PLimC , gave a promising outlook for the technical application of PLimC. Unfortunately, the onset of degradation ( T 5% = 225 °C, T 5% = temperature at 5% weight loss) of PLimC is rather close to its glass transition temperature ( T g ≈ 130 °C) .…”