The synthesis of Fe3O4/Co3O4–Cu photocatalyst for the treatment of real contaminated water by a new solar-based system

The present paper aims to develop a new off-grid system for treating real contaminated water by using Fe₃O₄/Co₃O₄–Cu as a photocatalyst. The novelty is to construct a solar-based system directed to synthesize the Fe₃O₄/Co₃O₄–Cu nano-photocatalyst and using for remove dyes from real wastewater evaluated in the mentioned off-grid photocatalysis-based system, simultaneously. Firstly, the different parts of the utilized laboratory system were introduced and the method of photocatalyst synthesis was also presented. Then, to analyze the photocatalyst purity and morphology, different analyses of FESEM, EDS, XRD, and TEM were utilized and UV–visible analysis was also used to measure COD (as an index of dye containment). Response Surface Methodology (RSM) was used for conducting the experiments. The included variables were the residence time of nanocomposite in the wastewater, the Dose, and the Cu amount that was used to enhance the absorbance activity of photocatalysts in different wavelengths, and the COD value was considered to be the response (R²) equal to 0.8294. In addition, a simulation based on an off-grid solar power system was developed using HOMER (Hybrid Optimization of Multiple Electric Renewables) Pro software, for a water treatment plant in the Bojnourd city, Iran. Based on XRD and EDS analysis, it was demonstrated that there is no considerable impurity in the synthesized samples. The optimal values for the factors of the Residence time, Cu amount, and Dose were demonstrated to be 46, 0.4, and 0.966, respectively, for obtaining the highest possible efficiency in removal.