Preparation and adsorption properties of magnetic Co0.5Ni0.5Fe2O4–chitosan nanoparticles

Magnetic chitosan microspheres were prepared by the emulsification cross-linking technique in the presence of glutaraldehyde as cross-linking agent, liquid paraffin as dispersant, and Span-80 as emulsifier. The optimal cross-linking time and Co0.5Ni0.5Fe2O4: chitosan ratio were determined. The morphology of particles was studied by different techniques. The adsorption characteristics were studied and the effect exerted by the initial concentration of methyl orange, the time of cross-linking, and the amount of the adsorbent was determined. It is found that the product obtained at the Co0.5Ni0.5Fe2O4: chitosan ratio 1: 4 and the crosslinking time 5 h has the uniform morphology. At room temperature, the Co0.5Ni0.5Fe2O4–chitosan magnetic composite has maximal adsorption for methyl orange at the dosage 20 mg.