Dottorato in SCIENZE CHIMICHE

Titolo della tesi: From waste to sorbents: recycling polymers for sample preparation and water remediation applications

Analytical chemistry plays a pivotal role in advancing sustainable development, acting both as a driver and a testing ground for the integration of sustainable practices into laboratory activities. A key aspect of this transition lies in the development of eco-friendly sample preparation strategies that reduce environmental impact without compromising analytical performance. This work presents the design and application of innovative adsorbent materials derived from recycled polymeric waste for use in solid-phase extraction and water remediation. The proposed materials, originating from biopolymer residues, industrial by-products, and post-consumer plastics, offer sustainable and cost-effective alternatives to conventional synthetic sorbents. Representative examples include extractive media fabricated from cellulose acetate (sourced from cigarette filters), polystyrene (from yogurt containers), and polylactic acid (from disposable products). A green and efficient synthetic protocol, combining microemulsion solidification with polymer dissolution–recycling, was developed to produce polymeric microspheres exhibiting excellent extraction capabilities for various classes of contaminants, including opioids, antibiotics, and pesticides in biological samples. Moreover, cellulose acetate microbeads were successfully employed in cartridge format for the remediation of organic pollutants from environmental waters. In a novel approach that merges recycling with modular design, functionalized LEGO® bricks were repurposed as reusable extraction platforms. The use of menthol as a thermo-responsive extraction medium, integrated into the LEGO®-based device, further expanded the versatility of the system, providing a simple, efficient, and solvent-saving procedure. Overall, this work demonstrates the feasibility and potential of integrating end-of-life polymeric materials into analytical workflows, opening new perspectives for customizable and sustainable sample preparation devices. The findings underscore the capability of recycled polymer-based sorbents to meet the rigorous requirements of modern analytical chemistry while advancing the principles of environmental sustainability.