Efficient adsorption removal and adsorption mechanism of basic fuchsin by recyclable Fe3O4@CD magnetic microspheres

Excessive discharge of dye wastewater has brought serious harm to human health and the environment. In this paper, a magnetic absorbent, ferroferric oxide@beta-cyclodextrin (Fe3O4@CD), was prepared for the efficient adsorption removal of basic fuchsin (BF) from dye wastewater, based on the special amphiphilicity of beta-CD and the strong magnetism of Fe3O4. A series of influence factors including the initial dye concentration, adsorbent dosage, temperature and pH were investigated, as well as the adsorption mechanism. The results show that Fe3O4@CD has the best adsorption and removal effect on BF dye at room temperature and neutral pH, when the initial concentration of dye is 25 mg/L and the adsorbent dosage is 100 mg. The adsorption behavior conforms to the pseudo-second-order kinetics and the Langmuir adsorption isotherm, and the adsorption process is spontaneously endothermic. Fe3O4@CD adsorbed with BF dye can be rapidly separated under an external magnetic field and then easily regenerated by HCl treatment. After 5 times of recycling, the removal rate of the prepared magnetic composite on BF dye is kept above 75%. This work will provide an economic and eco-friendly technology for the treatment of the actual dye wastewater.

Automated summary

A magnetic absorbent, Fe3O4@CD, prepared in this study showed efficient adsorption and removal of BF dye from wastewater, demonstrating promising application prospects in the treatment of dye wastewater.