This qualifying examination proposes the development and evaluation of polymer matrix composites based on thermoplastic polyurethane (TPU) containing inorganic particulate filler/reinforcement obtained from waste generated by the production of specialty fertilizers. The research stems from the need for the technological valorization of waste containing metallic constituents and the pursuit of polymeric materials with tunable properties through the incorporation of inorganic phases. The waste will be subjected to evaporation, washing, drying, calcination in an oxidizing atmosphere, and acid purification steps in order to obtain a purified oxide material. Subsequently, specimens of neat TPU and composites containing 5, 10, 20, and 30 wt% of the purified oxide will be produced via melt processing and injection molding. The materials will be characterized by chemical, elemental, structural, morphological, thermal, physical, and mechanical techniques, including X-ray fluorescence (XRF), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDS), thermogravimetric analysis and differential scanning calorimetry (TG/DSC), water absorption, density, and tensile, flexural, compressive, Izod impact, and Shore hardness tests.