Synthesis of Crosslinked Poly(Vinylphosphonic Acid) Particles by Water-in-Oil (W/O) Suspension Polymerization Method and Their Adsorption Properties of Metal Ions

Crosslinked poly(vinylphosphonic acid) (PVPA) particles were successfully synthesized from vinylphosphonic acid and a crosslinker by water-in-oil (W/O) suspension polymerization using three silicone oils. The structure, morphology, and size of the PVPA particles were confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy, and optical microscopy. The surface of the spherical particles was wrinkled, and their size ranged from 5 – 260 µm. The adsorption of divalent and trivalent metal ions (Cu2+, Zn2+, La3+, Tb3+, Lu3+) from aqueous solutions was studied using the synthesized PVPA particles under batch conditions at various metal ion concentrations and pHs for the first time. For all metal ions, pH-dependent adsorptions were observed. Partial charge neutralization of metal ions occurred because the PVPA particles are highly hydrophilic. The extraction efficiencies of La3+, Tb3+, and Lu3+ are higher than those of Cu2+ and Zn2+. The separation ability for La3+, Tb3+, and Lu3+ is not so high, but they can be used for the group extraction of these metal ions.