Preparation of zero-valent iron-nickle bimetallic composite for Se(IV) adsorption from aqueous solution

Se-79 is one of the important radionuclides in the safety evaluation of high-level radioactive waste repository due to its long half-life and highly fissionable radioactivity. Nanoscale zero valent iron-nickel bimetallic composite (Fe-0/Ni-0) was fabricated by liquid phase reduction method for Se(IV) adsorption from aqueous solution. The effects of pH, solid-liquid ratio, time, temperature, initial concentration of Se(IV) on the adsorption of Se(IV) by Fe-0/Ni-0 were investigated. Fe-0/Ni-0 was characterized by SEM, XPS, XRD, FT-IR, BET and Zeta potential, and the mechanism of removing Se(IV) was analyzed. The results showed that Fe-0/Ni-0 had a good removal effect on Se(IV). When pH was 3.5, the solid-liquid ratio was 0.3 g L-1, the reaction time was 40 min, the maximum adsorption capacity of Se(IV) by Fe-0/Ni-0 could reach 180 mg g(-1). The research results can provide a theoretical basis for the treatment of wastewater containing Se(IV).