Kayan, İremsuAyman Öz, Nilgün2025-05-292025-05-2920250268-25751097-4660https://doi.org/10.1002/jctb.7856https://hdl.handle.net/20.500.12428/30297This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution andreproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.BACKGROUND Municipal wastewater comprises both organic and inorganic contaminants. Especially in rural areas, conventional municipal treatment plants primarily focus on carbon removal; therefore, nutrient removal should be prioritized for preventing environmental pollution. Mixotrophic microalgae such as Nannochloropsis sp. have significant potential for both carbon and nutrient removal. However, microalgae-based wastewater systems can be affected by many parameters and, using response surface methodology and decision tree, a machine learning model can help to determine the optimal conditions for the systems to operate more efficiently. RESULTS The optimal removal conditions were determined by response surface methodology to be a light period of 21 h at an intensity of 8000 lx and a temperature value of 30 °C. Under these optimal conditions, the respective removal efficiency for chemical oxygen demand, total organic carbon, total Kjeldahl nitrogen, and orthophosphate was 53%, 34%, 87%, and 70%, respectively. Chlorophyll-a concentration increased by as much as 49%. Real municipal wastewater was used instead of synthetic wastewater, yielding closer approximations to real situations. CONCLUSION The present study has underscored innovative, data-driven approaches as core in ensuring sustainable wastewater management and sets a useful framework for future research, which could be done with the aim of refining the methods to enhance efficiency in treatment. © 2025 The Author(s). Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).eninfo:eu-repo/semantics/openAccessmunicipal wastewatermicroalgaeNannochloropsis sp.response surface methodologydecision treeoptimizationArticle10061244125610.1002/jctb.7856Q2WOS:0014525471000012-s2.0-105001541298Q1