Preparation and\nCharacterization of the MMT@Fe<sub>3</sub>O<sub>4</sub>@Ag Nanocomposite\nfor Catalytic Degradation of\nMethyl Yellow: Reaction Parameters and Mechanism Based on the Artificial\nNeuron Network

The montmorillonite@iron\noxide@silver (MMT@Fe<sub>3</sub>O<sub>4</sub>@Ag) nanocomposite, which\nis recyclable and exhibits high\ncatalytic activity, was evaluated for the degradation of methyl yellow\n(MY), a carcinogenic azo dye. For this purpose, MMT@Fe<sub>3</sub>O<sub>4</sub> was first synthesized via the coprecipitation method\nand then Ag was doped to MMT@Fe<sub>3</sub>O<sub>4</sub> via the chemical\nreduction method. MMT, MMT@Fe<sub>3</sub>O<sub>4</sub>, and MMT@Fe<sub>3</sub>O<sub>4</sub>@Ag were characterized by various techniques\nincluding scanning electron microscopy, Fourier transform infrared\nspectroscopy, X-ray diffraction, vibrating sample magnetometer, and\nthermal gravimetric analysis. The results illustrated that MMT@Fe<sub>3</sub>O<sub>4</sub>@Ag exhibited a higher catalytic ability than\nMMT@Fe<sub>3</sub>O<sub>4</sub> toward decolorization of MY with a\ndegradation efficiency of 100% in 10 min at pH 7.1 in the presence\nof sodium borohydride (NaBH<sub>4</sub>). Further, some parameters\nlike the amount of NaBH<sub>4</sub>, initial dye concentration, and\npH were also studied to determine optimum reaction conditions. MMT@Fe<sub>3</sub>O<sub>4</sub>@Ag could be easily separated and recycled from\nthe reaction medium using an external magnet. Thus, the Ag-doped MMT@Fe<sub>3</sub>O<sub>4</sub> nanocomposite proved to have good catalytic\nactivity, high MY degradation rate and reusability, and easy separation\nand simple synthesis method. These properties make it a promising\ncatalyst for the treatment of wastewater containing organic pollutants.\nIn addition, artificial neural network (ANN) simulation, which is\na mathematical model with an artificial intelligence algorithm, was\nused for the degradation process. This model was evaluated with the\nparameters used in the experiment as the input and output layers.\nLast, the degradation of MY with the synthesized catalyst into different\nproducts was demonstrated by high-performance liquid chromatography\n(HPLC) analysis.