One step preparation of ZnFe2O4/Zn5(OH)6(CO3)2 nanocomposite with improved As(V) removal capacity

ABSTRACTNovel adsorbents consisting of ZnFe2O4/Zn5(OH)6(CO3)2 (hydrozincite) nanocomposite materials were studied for efficient As(V) removal from water. Nanocomposites were synthesized by the co-precipitation of Zn and Fe salts in alkaline conditions. Depending on the Zn/Fe molar ratio, a variety of materials was produced with different ZnFe2O4/Zn5(OH)6(CO3)2 contents. The adsorbent’s efficiency for As(V) removal was enhanced proportionally to the percentage of Zn5(OH)6(CO3)2 content. The nanocomposite with 74 ± 7 wt% of Zn5(OH)6(CO3)2 provided a capacity of 18.4 μg As(V)/mg for residual concentration of 10 μg/L (pH 7) which is over twice that of an iron oxy-hydroxide prepared under similar conditions.