rapid exothermic adsorption of congo red dye on (ni0.25cu0.25zn0.50) fe2o4 nano composites; investigating operating parameters by response surface methodology

In the present study, (ni0.25cu0.25zn0.5) fe2o4 nanocomposites were synthesized through a co-precipitation method. they were characterized by fourier-transform infrared (ft-ir) spectroscopy, scanning electron microscope (sem), x-ray diffraction (xrd) analysis, and point of zero charge (phpzc) techniques. xrd analysis revealed mixed cubic and orthorhombic crystal structures in the nanocomposites. surface charge was determined by the ph drift method, and the phpzc was determined to be 6.1. the optimum operating parameters (oops) for the adsorptive removal of dye including adsorbent amount (40 mg), concentrations of congo red dye (16.0 mg/l), ph (4.5), temperature (25°c), and time (8.0 min), were used to design a half-factorial, 5-level central composite design. the removal efficacy was observed to be 97.59%. adsorption equilibrium was studied by various isotherm models, including freundlich, langmuir, temkin, and dubinin-radushkevich (d-r), at temperatures ranging from 303 to 323 k. it was observed that the langmuir model is well, with a maximum cr adsorption capacity of 55.19mg/g and a r² value of 0.900. the kinetic study followed pseudo-first-order kinetics. it demonstrated that the sorption process followed the pseudo-first-order kinetics. a thermodynamic study was also performed. the recycling and regeneration of adsorbent was also carried out. desorption experiments were also performed, and maximum desorption capacity was observed in the basic medium, and naoh showed maximum desorption efficacy. salt effects, including the matrix effect, were also observed, and maximum adsorption capacity was observed in the presence of a nacl matrix. conclusively, this study’s results showed that the synthesized nanocomposite is efficacious for dye removal and might prove to be an efficient and eco-friendly method for dye treatment processes.