A porous resin loaded with monoclinic or cubic hydrous zirconium oxide was prepared by incorporation of ZrOCl2 . 8H(2)O into porous spherical polymer beads followed by hydrolysis and hydrothermal treatment of the zirconium salt. Hydrous zirconium oxide appeared to deposit inside the pores with relatively large diameter. The adsorption capacity and distribution coefficients for As(III) and As(V) were determined by batch procedures. The hydrous zirconium oxide-loaded resin (Zr resin) showed a strong adsorption for As(V) at slightly acidic to neutral pH region while As(III) was favorably adsorbed at pH around 9 to 10. The removal of low concentrations of arsenic from the model effluents to meet the demand of Japanese industrial effluent standard (0.1 ppm) was successfully achieved by the column operation packed with the Zr resin. The Zr resin was regenerated by treatment of the column with 1 M sodium hydroxide followed by conditioning with 0.2 M acetate buffer solution. The amount of zirconium leached out during the adsorption and regeneration cycles was negligibly small and the column can be used repeatedly. (C) 2000 Elsevier Science B.V. All rights reserved.