Removal of Nickel from Plating Wastewater Using the Magnetic Flocculant PG-M

In this study, a new kind of magnetic particle functionalized biopolymer (PG-M) was applied to remove nickel from plating wastewater. The key parameters of pH, adsorption time, the mass of adsorbent, and shaking speed were investigated to optimize conditions. Batch experiments were conducted with actual samples collected from a manufacturer having an initial nickel concentration of 143.73 mg/L at pH 5. The highest removal efficiency of Ni2+ ions was greater than 99% when 1 g/L of the PG-M material was added to the solution (pH=10) and stirred at 200 rpm for 20 min. The desorption of this adsorbent was performed in a 0.1 M solution of HCl and the removal efficiency of Ni2+ ions unchanged after nine cycles. The Ni2+-loaded PG-M magnetic flocculant was easily separated from the solution by an external magnet.