REMOVAL OF ARSENIC(V) BY ZIRCONIUM(IV)-LOADED PHOSPHORIC ACID CHELATING RESIN

Abstract

Properties of Zr(IV)-loaded phosphoric acid chelating resin (RGP) as an adsorbent of As(V) were studied by means of the columnar method. Little leakage of Zr(IV) from RGP loaded with Zr(IV) (Zr-RGP) was observed within a wide pH range (pH 1.1–0.7 mol/L NaOH). Uptake of As(V) by Zr-RGP decreased with an increase in feeding-solution pH. The maximum capacity for As(V) was approximately 0.20 mmol/mL of wet resin (0.67 mmol/g of dry resin). Sodium chloride and sodium nitrate enhanced adsorption of As(V), and electrolytes in seawater also promoted the adsorption of As(V). Arsenic(V) adsorbed on Zr-RGP was quantitatively eluted with 0.4 mol/Ldium hydroxide, and repeated use of Zr-RGP was possible. In addition, Zr-RGP showed high selectivity to As(III). A large volume of 0.7 mol/L sodium hydroxide was needed to elute adsorbed As(III) quantitatively, indicating that As(III) was more strongly adsorbed by Zr-RGP than was As(V).

ACKNOWLEDGMENT

The authors are grateful to Nihon Yushi Co, Ltd for their gift of glycidyl methacrylate.