Sustainable Catalytic Upcycling of Plastic Waste: A Beverage Bottling Supply Chain Case Study

Thesis Abstract

Plastic waste accumulation and mismanaged end-of-life plastics pose critical environmental and economic risks to global beverage bottling supply chains. This study addresses the operational and environmental inefficiencies in converting post-consumer PET and multilayer packaging waste into high-value chemical feedstocks through catalytic upcycling within a real-world bottling context. The aim is to evaluate the technical feasibility, economic viability, and environmental benefits of catalytic upcycling pathways integrated into the beverage bottling supply chain, with objectives to (i) identify bottling-line plastics streams suitable for catalytic upcycling, (ii) compare catalyst systems and process conditions for depolymerization and selective monomer recovery, (iii) quantify process mass and energy balances and lifecycle environmental impacts, (iv) assess techno-economic performance and sensitivity to market plastics prices, and (v) formulate operational guidelines for scalable deployment in coordination with bottling partners. The study is anchored in the Resource-Based View and the Theory of Circular Economy to frame strategic feasibility and sustainability outcomes. The research adopts a mixed-methods design, combining quantitative process analyses with qualitative stakeholder insights. The population comprises three beverage bottling plants within a regional network, with a purposive sample of two plants actively piloting plastic upcycling pilot units (n=2) and one plant serving as a control (n=1). Data collection employs (i) bench-scale catalytic experiments using two representative catalysts—zeolite- or metal-supported catalysts (e.g., Ru/Al2O3 and ZSM-5) for PET glycolysis and transesterification, and (ii) a pilot-scale reactor operating at 1–5 kg/h throughput, documenting input-output streams, energy consumption, and catalyst life over 600 hours. Instrumentation includes gas chromatography–mass spectrometry (GC-MS) for product speciation, Fourier-transform infrared spectroscopy (FTIR) for polymer fingerprinting, differential scanning calorimetry (DSC) for monomer purity, and high-performance liquid chromatography (HPLC) for oligomer profiling; life cycle assessment (LCA) is conducted following ISO 14040/44 with process-based inventory and ReCiPe endpoint impact assessment. Economic evaluation leverages discounted cash flow analysis, levelized cost of product, and sensitivity analyses against feedstock price volatility and catalyst replacement costs. Data analysis utilizes analysis of variance (ANOVA) to compare catalytic performance across conditions, regression analysis to model conversion as a function of residence time and temperature, and scenario modeling to project supply chain gains under different market environments. The study anticipates findings that demonstrate higher selectivity toward commodity monomers and lower energy intensity for specific catalyst systems, as well as quantifiable reductions in greenhouse gas emissions and waste-to-resource conversion rates exceeding 40% when integrated with bottling operations. Anticipated contributions include a robust techno-economic-ecological framework for catalytic upcycling in the beverage sector, empirical evidence of the operational synergies between bottling facilities and plastics upcycling units, and a validated model for scale-up that integrates catalyst performance, process safety, and supply chain coordination. The research is expected to offer actionable recommendations for policy alignment, supplier collaboration, and infrastructure investment, including criteria for catalyst lifecycle management, feedstock sorting protocols, hydrogen and solvent management, and data-sharing mechanisms to enable circular material flows. The main conclusion posits that, under optimized catalytic systems and with integrated process control, beverage bottling networks can transform post-consumer plastics into high-value chemical precursors with competitive economic and environmental performance, thereby advancing circular economy objectives. Recommendations emphasize (i) the adoption of modular upcycling units adjacent to bottling campuses, (ii) establishment of standardized feedstock specifications and warranty-like guarantees for monomer quality, (iii) development of shared data platforms to monitor KPIs such as monomer yield, embodied energy, and GHG intensity, and (iv) policy incentives that reward verified cradle-to-cradle material loops.