Uptake of As(V) from aqueous solution by anionic clays type FeLDHs

The nature of the metal (Mg and/or Fe) salts, used as precursors during the synthesis process of layered double hydroxides, is used as a controlled variable synthesis parameter to obtain iron-containing anionic clay matrices with specific properties. The XRD and N-2 adsorption at 77 K analyses indicate that the structural and the textural features of the synthesized clays are influenced by the use of chloride, sulphate or nitrate, as different salts precursors, during the clay synthesis. The As(V) removal capacity of the tested clays is also a function of the nature of the used salt precursors, the maximum value, equal to nearly 72%, being reached when iron sulphate is used as precursor in the clay synthesis process. After calcination, the arsenate removal capacity is higher than 90% for all the samples.