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This study aims to present an accessible and sustainable proposal for development and evaluation of a activated carbon/CeO2 filter matrix for water defluoridation, with potential application in Brazilian regions and abroad with high fluorosis (dental and skeletal) incidence. Using a soft chemistry process, microwave assisted hydrothermal rout, cerium (VI) oxide nanostructures (ceria, CeO2) and its composites (activated carbon/CeO2 with 0%, 1%, 10% and 20% of CeO2) were prepared, using coconut (Cocos nucifera L.), from using coconut residue (Cocos nucifera L.), from the agribusiness in the interior of Paraiba. All synthesis, were proceeded at 120 °C, with different time intervals (1, 5, 15, 30 and 60 minutes, for the CeO2 obtention; and 30 minutes for composites – activated carbon/ CeO2). The structural, thermodynamic, morphological and adsorptive (fluorine) properties, were analyzed by X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDX), Infrared spectroscopy (IR), Thermogravimetric analysis (TGA), BET adsorption method, high resolution transmission electron microscopy (HR-TEM), high resolution scanning electron microscope (HR-SEM), respectively. The phase of the cerium oxide was determined by XRD analysis with planes ((1 1 1), (2 0 0), (0 2 2), (3 1 1), (2 2 2) and (4 0 0), in accordance with the cards JCPDS 34-0394), and the presence of the composite deposition was confirmed by EDX analysis. BET results showed for the best sample a surface area of (261 m2. g-1) for ceria particles, synthesized for 5 minutes. Microscopic analyzes (HR-SEM and HR-TEM) confirmed these results, presenting particle clusters of the order of 5nm, which justified its use for the composites production. Analyzes of fluoride concentration (direct and indirect methods), in composites obtaining, on a laboratory scale, were performed in triplicate with mean ± deviation and Tukey test with significant differences (p