Photocatalytic degradation of Acid Red 18 by synthesized AgCoFeO@Ch/AC: Recyclable, environmentally friendly, chemically stable, and cost-effective magnetic nano hybrid catalyst.

Chitosan (Ch) is a linear biodegradable natural carbohydrate polymer and the most appealing biopolymer, such as low-cost biodegradability, biocompatibility, hydrophilicity, and non-toxicity. In this case, Ch was utilized to synthesize AgCoFeO@Ch/Activated Carbon (AC) by the modified microwave-assisted co-precipitation method. The physical and chemical structure of magnetic nanocomposites was analyzed and characterized by Field Emission Scanning Electron Microscope (FESEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Energy Dispersive Spectroscopy (EDS), Diffuse Reflection Spectroscopy (DRS), Value stream mapping (VSM), Fourier transform spectroscopy (FTIR) and BET. The effects of various parameters on the removal of dye (Acid Red18), including catalyst dose, dye concentration, pH, and time were studied. Results showed that the highest removal efficiencies were 96.68 % and 84 % for the synthetic sample and actual wastewater, respectively, in optimal conditions (pH: 3, the initial dye concentration: 10 mgL, the catalyst dose: 0.14 gL, time: 50 min). Mineralization, according to the COD analysis, was 89.56 %. Photocatalytic degradation kinetics of Acid Red 18 followed pseudo-first order and Langmuir-Hinshelwood with constants of k = 0.12 mg L min and K = 0.115 Lmg. Synthesized photocatalytic AgCoFeO@Ch/AC showed high stability and after five recycling cycles was able to remove the pollutant with an efficiency of 85.6 %. So, the synthesized heterogenous magnetic nanocatalyst AgCoFeO@Ch/AC was easily recycled from aqueous solutions and it can be used in the removal of dyes from industries with high efficiency.