Synthesis of Polyacrylic Acid Stabilized Amorphous Calcium Carbonate Nanoparticles and Their Application for Removal of Toxic Heavy Metal Ions in Water

We report an efficient method for synthesis of poly(acrylic acid) stabilized amorphous calcium carbonate nanoparticles (ACC) and their application for removal of toxic heavy metal ions from aqueous solutions. The maxium removal capacities for Cd2+, Pb2+, Cr3+, Fe3+, and Ni2+ ions were found to be 514.62 mg g−1, 1028.21, 258.85, 320.5, and 537.2 mg g−1, respectively. The distinguishing features of the ACC nanoparticles in water treatment involve not only high removal capacities, but also decontamination of trace ions. Approximately 83.0% on average removal can be achieved in the treatment of polluted water containing trace amount of radioactive Eu3+ ions. A precipitation transformation mechanism is proposed to play a key role in such water treatment.