In this study, we conducted a comprehensive sustainability assessment of three porous chitosan particles as potential alternatives to petroleum-based ion exchange resins for water treatment. When normalized to mass produced, APCP was the most cost-effective variant, while TPCP and MPCP were significantly more expensive. However, when normalized to percent removal of methylene blue, MPCP exhibited the lowest environmental impacts, while TPCP had the highest impacts for most categories. Sensitivity analysis identified precursor costs, synthesis yield, chitosan and NaOH amounts, and electrical energy consumption as key drivers of sustainability. To enhance the sustainability of chitosan-based ion exchange resins, it is crucial to optimize synthesis conditions, implement process efficiency enhancements, optimize precursor quantities, and improve energy efficiency. This study provides valuable insights into the economic viability and environmental implications of chitosan-based ion exchange resins as alternatives to petroleum-based materials, emphasizing the importance of considering both production costs and treatment efficacy when evaluating their sustainability. Further research is recommended to optimize synthesis conditions, investigate the applicability of this framework to other biopolymers and contaminants, and explore the potential for scaling up the production of these sustainable alternatives.