Environmental Sustainability Assessment of Innovative Materials for Wastewater Treatment Using Life Cycle Assessment

Background and Purpose: This research forms part of the IN2AQUAS project (HORIZON-MSCA-2022-DN-01, Project: 101119555), which aims to apply Life Cycle Assessment (LCA) methodologies to assess and guide the environmental sustainability of innovative materials and processes for wastewater treatment. The study focuses on the synthesis and application of materials such as carbon quantum dots (CQDs), humic substances (HS), and humic-like substances (HLS). These materials are of growing interest because of their ability to enhance pollutant degradation through photochemical and adsorption processes. By quantifying their environmental footprints, the work aims to establish a framework to identify environmental trade-offs and optimize material development pathways. Methods: Primary experimental data collected within the IN2AQUAS consortium were used to construct detailed Life Cycle Inventories (LCIs) for the synthesis and application of selected materials. The LCA followed ISO 14040/44 standards and was implemented using the ReCiPe 2016 Midpoint (H) method in SimaPro software. Impact categories included energy use, emissions, and resource consumption, providing a multi-dimensional perspective on environmental performance. Results: Electricity consumption emerged as the dominant contributor across most impact categories, particularly under EU average energy conditions. Sensitivity analyses revealed that the carbon intensity of electricity significantly affects results, highlighting the influence of local energy systems. For chemical synthesis, reagents such as sodium hydroxide and the metal organic framework MIL-101-Fe were identified as substantial contributors to overall impacts. Conclusions: The results offer an early yet comprehensive understanding of the environmental implications of integrating innovative materials into wastewater treatment systems. Electricity and reagent production represent key environmental hotspots, emphasizing the need for cleaner energy integration, optimized process design, and material substitution strategies. The findings contribute to establishing sustainability-oriented criteria for future material development and pilot-scale evaluations.