Adsorption of Bismarck Brown by Iron Oxide Nanosphere and Its Modified Form

In the present study, adsorption of Bismarck Brown (BB) dye onto iron oxide nanospheres (IONs) and modified IONs by HCl from aqueous solution was investigated. The IONs was synthesized by solvothermal method and then modified by HCl. The high magnetic properties of both adsorbents lead to facial separation from aqueous solution by an external magnet. The results show that the modification of adsorbent cause higher adsorption capacity for removal of BB from aqueous solution. The prepared adsorbents were characterized by SEM, XRD, FTIR, and ATR-IR techniques. The adsorption kinetic and equilibrium data were fitted with different models. The results show that the equilibrium and kinetic data were best fitted with Langmuir–Freundlich isotherm and fractal-like pseudo-second-order kinetic model, respectively. The effects of pH and temperature have also been investigated.