Facile method for the synthesis of Fe3O4@ HCP core-shell porous magnetic microspheres for fast separation of organic dyes from aqueous solution

A novel type of porous magnetic microsphere (Fe3O4@HCP) was firstly synthesized just via one-step Friedel-Crafts alkylation promoted by FeCl3. This universal and facile method to fabricate porous magnetic microspheres possesses distinct advantages such as cheap reactants, mild reaction conditions, a short reaction time and a simple post-treatment process. The core-shell spheres with a well-defined and uniform morphology possess a high Brunauer-Emmett-Teller specific surface area (770 m(2) g(-1)). Besides, the magnetization saturation value reaches up to 18 A m(2) kg(-1) which is high enough to separate Fe3O4@HCP from aqueous solution. Fe3O4@HCP possesses fast adsorption kinetics and an excellent adsorption capacity for organic dyes: methyl orange (211 mg g (1)) and fuchsin basic (231 mg g(-1)). The adsorption-saturated Fe3O4@HCP composites can be easily collected by an external magnetic field and reused at least 3 times after simple Soxhlet extraction and drying.