Phosphate removal from wastewater using novel renewable resource-based, cerium/manganese oxide-based nanocomposites

Nanocomposites containing mixed metal oxides show excellent phosphate removal results and are better compared to individual metal oxides. In this research, cerium/manganese oxide nanocomposites, embedded on the surface of modified cellulose pine wood shaving, were synthesized by a simple technique that is both eco-friendly and economically feasible. No toxic or petroleum chemicals were employed during preparation. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), surface area analysis, and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy were performed to study the shape and size of nanocomposites as well as composition of elements present on the surface of the nanocomposites. Adsorption isotherm (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) and kinetic studies (pseudo first and second-order, Elovich and Weber-Morris) were carried out to determine the adsorption mechanism for phosphate removal from contaminated water. The maximum adsorption capacity of nanocomposites was found to be 204.09 mg/g, 174.42 mg/g, and 249.33 mg/g for 100 mg, 300 mg, and 500 mg, respectively. The results indicate that the nanocomposites were able to decrease the phosphorus concentration from 10 to 0.01 ppm, below the threshold limit required by EPA guidelines in the USA. We also demonstrated that the media could be regenerated and reused five times without loss of performance.