Nitrate adsorption from aqueous solution by MII-Al-CO3 layered double hydroxide

Hydrotalcite compounds were found to have high anion adsorption capacity that enhances their capability to remove anionic contaminants from aqueous systems. In this study, the adsorption of nitrates by various layered double hydroxides (LDHs), such as Mg-Al and Zn-Al, was investigated. The nature and content of divalent cations in LDHs have strong influence on the adsorption process. Calcined Mg-Al LDH with an Mg/Al molar ratio of 3.0 showed higher adsorption capacity compared to other calcined LDHs. The adsorption phenomenon has been well supported by x-ray diffraction and infrared studies.