Retention of Pb(II) by a Low-Cost Magnetic Composite Prepared by Environmentally-Friendly Plasma Technique

Abstract

A low-cost magnetic composite (gelatin/Fe₃O₄) is prepared by Fe₃O₄ nanoparticles treated with gelatin using an environmentally-friendly plasma technique, and is applied for the removal of toxic Pb(II) ions from aqueous solutions. Not only that it originates from cheap and abundant raw materials, the gelatin/Fe₃O₄ composite also has advantages in convenient magnetic separation from aqueous solution, which can hopefully reduce water treatment expenses. The batch experimenta results indicate that the maximum adsorption capacity (q_max) of Pb(II) on this gelatin/Fe₃O₄ composite is ∼115 mg/g, higher than most of the other bare and modified magnetic materials, which is considered to be attributed to the strong interaction between Pb(II) and the abundant functional groups introduced by gelatin. When exposed to acidic solutions, the dissolution of the gelatin/Fe₃O₄ nanoparticles is minimal due to the protective character of the grafted gelatin layer on the Fe₃O₄ nanoparticles. The utilization of the plasma technique in the synthesis of magnetic composite agrees well with the tenet of green chemistry. It is promising that this gelatin/Fe₃O₄ composite would become an efficient and economic material for heavy metal ion removal in the practical environmental remediation.

Keywords:

• gelatin/Fe₃O₄ composite
• magnetic separation
• Pb(II)
• surface modification

ACKNOWLEDGEMENTS

Financial support from the 973 project of the Ministry of Science and Technology (2011CB933700) and National Natural Science Foundation of China (21007074; 21107115; 20971126) are acknowledged.