Preparation of magnetic Fe3O4 particles modified sawdust as the adsorbent to remove strontium ions

Magnetic Fe3O4 particles modified sawdust (MCS) was prepared by using chitosan as the bridging reagent and characterized by FTIR analysis, and the results indicated that sawdust was successfully modified by magnetic Fe3O4 particles by connection of chitosan. The results obtained from the strontium ions adsorption experiments showed that the MCS was an effective material to remove strontium ions from aqueous solutions. And most importantly, the adsorption process was safely and easily controlled, the separation of MCS from solutions after adsorption was fast because of the magnetic modification. The adsorption of strontium ions by MCS was affected by pH, background electrolyte, adsorbent dosage and contact time. The adsorption process could achieve equilibrium in 30 min, and the maximum adsorption capacity studied at different initial concentrations was 12.59 mg/g. The adsorption process was a physical process which could be approved by the adsorption free energy and well fitted by the pseudo first order model.

► MCS was prepared and used to remove radioactive strontium ions.
► Adsorption is an easy controlled because of the magnetic character of the MCS.
► The MCS could be separated after adsorption because of the magnetic modification.
► Use chitosan as the bridging reagent to connect sawdust and magnetic Fe3O4 particles.