The removal of arsenic (As) species, such as As(III) and As(V), from water by molybdate-impregnated chitosan beads (MICB) in both batch and continuous operations was studied. The effects of pH, temperature, coexisting ions, and arsenic concentrations were studied in batch tests. Studies oil the kinetic adsorption of MICB, the recovery of arsenic by the desorption solution, and the reuse of MICB were also carried out. The practicality and efficiency of an MCIB-packed column oil arsenic removal were evaluated in a continuous system oil industrial arsenic-containing wastewater discharged during the manufacture of GaAs supports. The results indicate that MICB favor the adsorption of both As(V) and As(III). The optimal pH value for As(III) and As(V) removal was 5. Tile adsorption of arsenic oil the MICB is most likely an exothermic reaction. The effect of coexisting ions was varied and depended oil their concentrations and species. The optimal desorption solution for arsenic recovery was 1 M H2SO4, which resulted in a 95% efficiency for As(Ill) and 99%) for As(V). In the continuous tests, the MICB-packed column exhibited excellent arsenic removal from wastewater without any pretreatment. These results provide strong evidence of the potential of MICB for removing As from industrial wastewaters. (C) 2008 Elsevier Ltd. All rights reserved.