Ionic liquid modified molybdenum disulfide and reduced graphene oxide magnetic nanocomposite for the magnetic separation of dye from aqueous solution.

A novel ionic liquid (IL) modified magnetic nanocomposite (mag-MoS2-RGO), which was composed of molybdenum disulfide (MoS2) and reduced graphene oxide (RGO), was firstly synthesized and characterized (mag-MoS2-RGO-IL). Compared with mag-MoS2-RGO, the mag-MoS2-RGO-IL exhibited the higher adsorption capacity of 143.9 mg/g for methylene blue (MB) under optimum conditions. Experimental results were imitated by adsorption isotherms and kinetic models, revealing a monolayer adsorption on the homogeneous surface governed by chemisorption. The removal rate was maintained 78% after 5 cycles of regeneration, indicating its good reutilization. Methodological study suggested that the method possessed excellent repeatability, precision and stability. The recoveries from the real samples were in the range of 87.0-98.8% with relative standard deviation of ≤5.2%. Benefiting from composite structure and magnetic Fe3O4, the stable magnetic adsorbent can be quickly separated from aqueous solution. All of above proves that the prepared mag-MoS2-RGO-IL has great application potential in dye separation.