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This thesis investigates the potential of phytofiltration as a nature-based solution for removing per- and polyfluoroalkyl substances (PFAS) from Swedish municipal wastewater. A systematic literature review was combined with a capacity-limited dynamic mass balance model developed in MATLAB to evaluate PFAS removal mechanisms in constructed wetlands. The model incorporated a finite plant uptake capacity (Qmax) derived from the adsorption capacity concept used in phytoremediation studies, coupled with a first-order uptake rate within a continuously stirred tank reactor (CSTR) framework. Simulations were conducted over a 24-week growing season for three emergent aquatic plant species: Carex rostrata, Cyperus alternifolius, and Eriophorum angustifolium. The results demonstrate that long-chain PFAS are removed more effectively than short-chain PFAS, with removal efficiencies ranging from 61% to 95% for long-chain compounds and 12% to 27% for short-chain compounds. Cyperus alternifolius exhibited the highest long-chain PFAS removal (95%), while Carex rostrata showed highest short-chain PFAS removal (27%). Eriophorum angustifolium exhibited the lowest overall performance. The cumulative uptake analysis revealed that plant uptake remained below the estimated Qmax for Carex rostrata and Eriophorum angustifolium throughout the modelled growing season. A sensitivity analysis showed variation in Qmax had a comparatively limited influence on predicted removal, while the model was more sensitive to variation in the plant uptake rate constant kU. The findings suggest that phytofiltration can contribute to PFAS removal in municipal wastewater, particularly for long-chain compounds. However, it is unlikely to function effectively as a standalone treatment method due to low removal efficiencies for short-chain PFAS. Phytofiltration may be more suitable as a complementary technology within hybrid treatment systems. Future research should focus on field validation of uptake rate constants in Swedish CWs, investigation of additional plant species, and integration with other treatment technologies.