In this work, we report solid-state synthetized defective Bi2O3 containing Bi(V) sites as effective and recyclable arsenic adsorbent materials. Bi2O3 was extensively characterized, and structure-related adsorption processes are reported. Both As(V) and As(III) species-adsorption processes were investigated in a wide range of concentrations, pH values, and times. The effect of several competing ions was also tested together with the adsorbent recyclability.